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1

Soil C:P Ratio along Elevational Gradients in Picea schrenkiana Forest of Tianshan Mountains

Cao Y., Wang Y., Xu Z.

Polish Journal of Ecology

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2018

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Vol. 66, nr 4

325--336

EN

Forest soils potentially store a large pool of carbon and phosphorus. A deep understanding of the total carbon and phosphorus stock in forest soils is vital in the assessment of the nutrients dynamics in forest ecosystems. This study examined the effects of elevation, soil depth, and climatic variables, specifically mean annual temperature (MAT) and mean annual precipitation (MAP), on soil carbon and organic phosphorus in Schrenk's spruce (Picea schrenkiana) forest at Tianshan Mountains. Results showed that soil organic carbon (SOC) significantly increased while organic phosphorus decreased with elevation. Interestingly, carbon increased faster with increasing elevation in the alluvial horizon than in the leached horizon, demonstrating the important role of deep soils in carbon sequestration potential. SOC concentration decreased with soil depth, whereas phosphorus concentration initially decreased and then increased. SOC had no significant relationships with MAT and MAP, whereas phosphorus concentration decreased with MAT. Similar to the impacts of MAT and MAP on SOC, these two climatic variables also exerted no significant influence on C:P ratio.

2

A method for measuring the quality parameters of image intensifier based on projecting phase-shifting gratings

Sun S., Cao Y., Chen C., Fu G., Wang Y., Xu X.

Optica Applicata

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2018

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Vol. 48, nr 1

39--51

EN

A method for measuring the quality parameters of image intensifier based on projecting phase-shifting gratings is proposed. A set of designed phase-shifting gratings are projected into the measuring system orderly to obtain the magnification parameter of the measured image intensifier, and the phase caused by the measured image intensifier. After obtaining the referential phase caused by only the magnification of the measured image intensifier, the phase caused by the distortion of the measured image intensifier is extracted by phase calculating and phase unwrapping. Both the global distortion and the partial distortion of the measured image intensifier can be measured by phase-to-distortion matching at the same time. The experimental results show that the proposed method can measure the multiple quality parameters of image intensifier effectively.

3

Blasting control and monitoring system for safety improvement during blasting operation. A case study in Guilaizhuang gold mine

Cao Y., Ji H., Zhang T.

Mining Science

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2018

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Vol. 25

33--48

EN

The design of a blasting monitoring and control system and its practical application in a blind gallery named Dongguabang in Guilaizhuang gold mine in China was presented in the paper. Based on reason analysis of blasting accidents occurring in metal mines, a blasting accident model is established in order to explain the process of the accident and its direct reasons. Also, effective approaches for preventing blasting accidents and avoiding casualties are achieved by controlling unsafe behaviour of workers and elimination of the critical "touch". Combined with analysis of safety ergonomics of blasting devices, all these make a joint contribution to providing theoretical instruction and references to establishment and design of blocking functions of blasting monitoring system. A set of blasting monitoring and control system is implemented, and equipped with blocking functions when unsafe behaviour and conditions appear. Tests of the monitoring system are carried out in the Donguabang heading of Guilaizhuang gold mine. It is documented that the blocking functions and the central computer platform run well during the tests. Test results reveal that blasting monitoring and control system and its functions are able to ensure safety and fulfil work requirements in Guilaizhuang gold mine.

4

Study on distribution of CO and concentration prediction in blind gallery after blasting operation

Cao Y., Ji H., Zhang Y., Li S.

Archives of Mining Sciences

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2018

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Vol. 63, no. 2

283--300

EN

It is meaningful to study the issues of CO migration and its concentration distribution in a blind gallery to provide a basis for CO monitoring and calculation of fume-drainage time, which is of a great significance to prevent fume-poisoning accidents and improve efficiency of an excavation cycle. Based on a theoretical analysis of a differential change of CO mass concentration and the CO dispersion model in a fixed site, this paper presents several blasting fume monitoring test experiments, carried out with the test location to the head LP in arrange of 40-140 m. Studies have been done by arranging multiple sensors in the arch cross-section of the blind gallery, located at the Guilaizhuang Gold Mine, Shandong Province, China. The findings indicate that CO concentrations in the axial directions are quadratic functions with the Y and Z coordinate values of the cross-section of the blind gallery in an ascending stage of CO time-concentration curve, with the maximum CO concentrations in Y = 150 cm and Z = 150 cm. Also, the gradients of CO concentration in the gallery are symmetrical with the Y = 150 cm and Z = 150 cm. In the descending stage of CO time-concentration curve, gradients of CO concentration decrease in lateral sides and increase in the middle, then gradually decrease at last. The rules of CO concentration distribution in the cross-section are that airflow triggers the turbulent change of the CO distribution volume concentration and make the CO volume concentration even gradually in the fixed position of the gallery. Moreover, the CO volume concentrations decrease gradually, as well as volume concentration gradients in the cross-section. The uniformity coefficients of CO concentration with duct airflow velocities of 12.5 m/s, 17.7 m/s and 23.2 m/s reach near 0.9 at 100-140 m from the heading to the monitoring spot. The theoretical model of a one-dimensional migration law of CO basically coincides with the negative exponential decay, which is verified via fitting. The average effective turbulent diffusion coefficient of CO in the blind gallery is approximate to 0.108 m2/s. There are strong linear relationships between CO initial concentration, CO peak concentrations and mass of explosive agent, which indicates that the CO initial concentration and the CO peak concentration can be predicted, based on the given range of the charging mass. The above findings can provide reliable references to the selection, installation of CO sensors and prediction of the fume-drainage time after blasting.

PL

Badania migracji, rozpływu i rozkładu stężenia CO w ślepym wyrobisku są niezbędne, stanowią one bowiem podstawę do skutecznego monitorowania poziomu CO i obliczania czasu niezbędnego na usunięcie z wyrobiska szkodliwych gazów – jest to kwestia kluczowa dla zapobiegania wypadkom związanych z zatruciem spalinami oraz dla planowania przebiegu prac wydobywczych. W oparciu o teoretyczną analizę zmian stężenia masowego CO i wykorzystując model dyspersji gazu w stałym punkcie, w pracy przedstawiono wyniki eksperymentów przeprowadzonych w ramach monitorowania stężeń gazów powybuchowych w wyrobisku LP na odległości 40-140 m od czoła wyrobiska. Badania prowadzono przy wykorzystaniu zestawu czujników rozmieszczonych w wybranych punktach ślepego wyrobiska w kopalni złota Guilaizhuang, w prowincji Shandong, Chiny. Wyniki badań wskazują, że stężenia CO w kierunkach poosiowych są funkcjami kwadratowymi wartości współrzędnych Y i Z przekroju przekroju ślepego wyrobiska w zakresie krzywej opadającej na wykresie opisującym zależność stężenia CO od czasu, przy czym maksymalne stężenia CO stwierdzono dla Y =150 cm i Z = 150 cm. Ponadto, wykazano że gradienty stężenia CO w wyrobisku są symetryczne dla Y =150 cm i Z =150 cm. W zakresie krzywej rosnącej na wykresie zależności stężenia CO od czasu gradienty stężenia CO wykazują spadek w końcowych regionach wykresu, w środkowej części wykresu notuje się jego wzrost, po czym znów następuje spadek. Na rozkład stężenia CO w tym przekroju wpływ ma fakt że przepływ powietrza wywołuje turbulentne zmiany stężenia objętościowego CO, następnie stężenie objętościowe maleje systematycznie w dalszych częściach wyrobiska. Ponadto, stwierdzono że stężenie CO a także gradienty stężenia objętościowego w przekroju maleją stopniowo. Współczynniki wyrażające równomierność stężenia CO przy przepływach powietrza z prędkością 12.5 m/s 17.7 m/s i 23.2 m/s osiągają wartość 0.9 w punkcie kontrolnym odległym od wyrobiska o 100-140 m. Teoretyczny model jednowymiarowego rozpływu CO zasadniczo pokrywa się z wzorem zależności wykładniczej z wykładnikiem ujemnym, co zostało potwierdzone w procedurze pasowania. Średnia wartość współczynnika dyfuzji CO dla przepływu turbulentnego w ślepym wyrobisku wyniosła 0.108 m2/s. Stwierdzono istnienie silnej zależności liniowej pomiędzy początkowym stężeniem CO, szczytową wielkością stężenia oraz masą użytego materiału wybuchowego, która wskazuje na możliwość prognozowania początkowego i szczytowego stężenia CO w oparciu o zakres wielkości użytego ładunku wybuchowego. Przedstawione wyniki badań stanowić mogą wiarygodną podstawę dla wyboru rodzaju i miejsca zainstalowania czujników CO oraz do prognozowania czasu wymaganego na usuniecie szkodliwych gazów po zakończeniu prac strzałowych.

5

Social Responsibility, Internal Governance and Manufacturing Growth

Cao Y., You J., Shi Y., Hu W.

Problemy Ekorozwoju

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2017

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Vol. 12, nr 1

41--54

EN

This article presents a structural equation model for exploring the impact of social responsibility, which been divided into responsibility for the internal stakeholder and responsibility for the external stakeholder, as well as internal governance on Chinese manufacturing growth on the basis of data collected from 500 manufacturing enterprises in the East region of China. Our results show that both social responsibility and internal governance have a positive impact on manufacturing growth and promote sustainable development in manufacturing. In addition, social responsibility has a positive impact on internal governance, and the internal governance plays a partial intermediary role in the impact of social responsibility on manufacturing growth. These findings signify that it is important for Chinese Manufacturing to undertake Social Responsibility, and it can provide a beneficial guidance for Chinese Manufacturing Growth and help strengthen the competitive advantage of manufacturing industry.

PL

Artykuł przedstawia model równania strukturalnego odnoszący się do społecznej odpowiedzialności, wyróżniając w jej ramach odpowiedzialność za wewnętrznego oraz zewnętrznego akcjonariusza i wewnętrzne zarządzanie w kontekście wzrostu produkcji w Chinach, w oparciu o informacje uzyskane z 500 firm pochodzących ze wschodniej części kraju. Przeprowadzona analiza pokazuje, że zarówno społeczna odpowiedzialność, jak i wewnętrzne zarządzanie, mają pozytywny wpływ na wzrost produkcji i promocję zrównoważonego wytwarzania. Ponadto społeczna odpowiedzialność ma pozytywny wpływ na wewnętrzne zarządzanie, a w oddziaływaniu społecznej odpowiedzialności na wzrost produkcji, wewnętrzne zarządzane odgrywa po części rolę pośrednika. Uzyskane rezultaty wskazują, że społeczna odpowiedzialność jest ważna, może pełnić rolę dobrego doradcy w kontekście wzrostu chińskiej produkcji i pomóc w zwiększeniu konkurencyjnej przewagi dla przemysłu wytwórczego.

6

Risk of the maritime supply chain system based on interpretative structural model

He J., Xiong W., Cao Y.

Polish Maritime Research

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2017

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S 3

28--33

EN

Marine transportation is the most important transport mode of in the international trade, but the maritime supply chain is facing with many risks. At present, most of the researches on the risk of the maritime supply chain focus on the risk identification and risk management, and barely carry on the quantitative analysis of the logical structure of each influencing factor. This paper uses the interpretative structure model to analysis the maritime supply chain risk system. On the basis of comprehensive literature analysis and expert opinion, this paper puts forward 16 factors of maritime supply chain risk system. Using the interpretative structure model to construct maritime supply chain risk system, and then optimize the model. The model analyzes the structure of the maritime supply chain risk system and its forming process, and provides a scientific basis for the controlling the maritime supply chain risk, and puts forward some corresponding suggestions for the prevention and control the maritime supply chain risk.

7

A conceptual model of excellent performance mode of port enterprise logistics management

He J., Xiong W., Cao Y.

Polish Maritime Research

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2017

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S 3

34--40

EN

Port as one of the key hubs of international logistics, which has become the main part and the base of global logistics management. The port enterprises, plays an important role in the global supply chain. However, due to the lack of understanding in port supply chain management, coordination between the port enterprises, the integration of business process is not perfect, the lack of information sharing between various organizations, ports enterprises usually failed to fully play its positive role. Based on this, the paper makes the port enterprises as the research object, and introduces the excellent performance mode into the port enterprises. In order to study the port enterprises how to carry out effective quality management, and formation the coordination and integration of upstream and downstream of enterprises, so as to realize the competitive advantage in port logistics.

8

Influence of controlled dispersion on rheology of swelling clay suspensions in the presence of coal flotation reagents

Zhang M., Cao Y., Chen Y., Yu W.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

1148--1160

EN

Swelling clay minerals, which are innately capable of dispersing into thin flakes in water, can significantly depress coal flotation. Some researchers partially attribute depression to pulp viscosity increments. This study sought to understand the role of swelling clay minerals in fine coal flotation, by investigating the rheological behavior of bentonite suspensions under controlled and uncontrolled dispersion conditions. The effect of collector, frother, and solution pH on rheological properties of the pulp was studied. Findings showed that at a natural pH, Newtonian flow properties were displayed when bentonite was directly added into a swelling suppressed solution containing calcium ions. The same process was repeated under uncontrolled conditions, and the suspensions transferred from Newtonian to non-Newtonian flows with pseudo-plastic characteristics, depending on the solid density. Further, pH value, methyl isobutyl carbinol (MIBC) and kerosene had the potential to alter the rheological behavior of controlled and uncontrolled systems, especially pH value in the uncontrolled system.

9

Flotation behavior of nickel sulfide ore in a cyclonic flotation column

Deng L., Li G., Cao Y., Ma Z.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

770--780

EN

This study aimed to show the flotation behavior of a nickel sulfide ore in a cyclonic flotation column. The flotation experiments were carried out using a sample of nickel sulfide ore obtained from a mineral processing plant of China. Representative samples collected from the feed, concentrate, tailing, and circulation middling were sieved using a cyclonic particle analyzer to collect different size fractions for analysis. The function of the column cyclonic zone of was evaluated by comparing the quality of tailing and circulation middling. The flotation results showed that the concentrate with Ni grade of 1.78% and recovery of 65.56% was obtained under given test conditions. The content of main sulfide minerals and coarse particles in the circulation middling was higher than that in the tailing. The results indicated that, unlike conventional cyclone classification, separation achieved in the cyclonic zone of the column was not dependent on the particle size and density. Sulfide minerals with good floatability were easily captured by bubbles and moved toward the center of the column, even if these particles were coarser and heavier.

10

Adsorption behavior of Zn(II) onto natural minerals in wastewater. A comparative study of bentonite and kaolinite

Chai W., Huang Y., Su S., Han G., Liu J., Cao Y.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

264--278

EN

In order to remove the harmful metal ions in lead-zinc mineral processing wastewater, two natural clay minerals (bentonite and kaolin) were used as adsorbents and Zn(II) ions were the emphasis in this work. The adsorption behaviors including kinetics and isotherms were investigated by batch experiments. In addition, the adsorption mechanisms were studied by means of zeta potential testing, optical microscope and XRD analysis. The results show that the adsorption process can be best described as the pseudo-second order kinetic model. The adsorption equilibrium data of bentonite and kaolinite can be respectively fitted best by Langmuir and Freundlich models. Thermodynamic studies display that the adsorption of Zn(II) onto clays is non-spontaneous and endothermic. The maximum capacity of Zn(II) adsorbed on bentonite and kaolinite respectively reaches to 79.2 mg·g-1 and 6.35 mg·g-1 at 25 °C. The structural differences of bentonite and kaolinite result in the differences in adsorption behavior and mechanism. The interaction mechanisms of Zn(II) with bentonite and kaolinite involve electrostatic attraction, cation exchange, surface complex and precipitation. Bentonite as adsorbent has the potential to remove Zn2+ better than kaolinite.

11

Abnormal phase removing method in phase measuring profilometry

Xu X., Cao Y., Chen C., Cao S., Peng K.

Optica Applicata

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2017

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Vol. 47, nr 1

85--95

EN

An abnormal phase removing method in phase measuring profilometry is proposed. In the five equal shifting phase steps algorithm, the shifting phase might be extracted from the deformed patterns captured by CCD camera. But there may be some errors introduced by a digital fringe projector and CCD camera in these deformed patterns. The impurity of the deformed patterns may lead to four classes of abnormalities when extracting the shifting phase. These abnormalities may cause the wrong shifting phase extraction by which the reconstructed object might be misshapen or anamorphic, or even in failure. By this proposed method, the above abnormalities can be removed, and the shifting phase can be auto-extracted precisely from the impure deformed patterns without knowing its value. Experimental results verify the feasibility and effectiveness of the proposed method.

12

Research on vertical change trend of environmental indicators of mining face and its assessment in gold mine

Cao Y., Ji H., Pei F.

Mining Science

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2017

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Vol. 24

99--115

EN

This paper presents interpretation of results of a series of monitoring tests on O2, CO2, dust, noxious gases, microclimate, noise and illumination, conducted in seven mining faces of a metal mine, with vertical depths of -30 m, -70 m, -110 m, -150 m, -190 m, -230 m and -300 m. Through research on a vertical trend of a particular factor, several findings can be concluded as follows: concentration of CO2 rises up, while O2 decreases with deeper mining depth; concentrations of noxious gases increase with the deeper mining depth; dust amount exceeds seriously the limit, and grows linearly with the mining depth; dry-bulb temperature, effective temperature and relative humidity demonstrate a linear increase with the mining depth; sound pressure level in mining faces seriously exceed the limit value, and may cause a great harm to miners; illumination values in most mining faces are lower, comparing to the standard. Comprehensive evaluation of environmental quality of faces is carried out by introducing a model of grey clustering combined with G1-method, to determine the weight values and classify quality of the working environment. Results reveal that the environmental quality grade (EQG) of mining faces decrease with the increasing depth. In particular, EQG is excellent when above -150 m exploitation level, at which it becomes mediocre, and changes to bad when below -150 m.

13

Evaluation of Automobile Manufacturing Enterprise Competitiveness from Social Responsibility Perspective

Cao Y., You J., Shi Y., Hu W.

Problemy Ekorozwoju

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2016

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Vol. 11, nr 2

89--98

EN

The article proposed an index system based on social responsibility, including the main index of Employee dimension, Government dimension, Customer dimension, Business partner dimension, Ecological benefits dimension and the sub- index which comprised 18 indexes to evaluate the automotive manufacturers competitiveness. Based on the index system, an evaluation model integrates by extension theory and AHP and groups eigenvalue method (GEM) was introduced. Using established evaluation system and evaluation model, an empirical analysis is elaborately explained. The key result of the evaluated show that the index system and evaluation model built in this research not only can overcome the shortcomings of other methods requiring large data but also can clear the mechanisms and determinants of how CSR produces competitiveness, so it has a good applicability in automobile manufacturing enterprise competitiveness evaluation.

PL

Artykuł przedstawia system wskaźników oparty na społecznej odpowiedzialności, uwzględniający główne wskaźniki na poziomie zatrudnienia, rządu, konsumenta, partnera biznesowego, korzyści ekologicznych i zawierający 18 elementów pozwalających ocenić konkurencyjność branży samochodowej. Na systemie wskaźników oparto ocenę modeli integrujących teorię rozszerzenia, AHP i GEM. Korzystając z przyjętego systemu i modelu oceny przeprowadzono następnie badania empiryczne. Uzyskane rezultaty pokazują, że zastosowana metodologia po-zwala nie tylko rozwiązać problemy wynikające z niedociągnięć innych metod wymagających dużych baz danych, ale także pozwala na lepsze zrozumienie mechanizmów i uwarunkowań odnoszących się do tego, w jaki sposób koncepcja społecznej odpowiedzialności biznesu wpływa na konkurencyjność, a poprzez to znakomicie nadaje się do zastosowania w ocenie konkurencyjności branży samochodowej.

14

Designing a Mixed Evaluating System for Green Manufacturing of Automotive Industry

Cao Y., You J., Wang R., Shi Y.

Problemy Ekorozwoju

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2016

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Vol. 11, nr 1

73--86

EN

The article proposed, from a sustainable development perspective, an index system based on Sustainability Balanced Scorecard (SBSC), including the main index of Financial, Internal process, Customer, Learning and growth, Social and the sub- index which comprised 28 indexes to evaluate the Green Manufacturing (GM) of automotive industry. Based on the index system, an evaluation model integrates by back-propagation artificial neural network (BPANN) and genetic algorithm (GA) was introduced. Using established model and indicators evaluated GM in four automotive companies; the key result of the evaluated show that: China’s automotive manufacturing enter-prises still have big room for improvement in respect of customer satisfaction, resource consumption, community service, low-carbon activities etc., so the strategy and management activities that put much pressure on these respect are necessary.

PL

W artykule zaproponowano wykorzystanie systemu wskaźników opartych na Zrównoważonej Karcie Wyników (Sustainability Balanced Scorecard – SBSC). Zgodnie z koncepcją rozwoju zrównoważonego uwzględniono na-stępujące główne wskaźniki: finansowy, procesów wewnętrznych, klienta, wzrostu i uczenia się, społeczny, a także 28 podwskaźników. Celem była ocena Zielonej Produkcji (Green Manufacturing – GM) w przemyśle mo-toryzacyjnym. Wprowadzono model oceny oparty na systemie wskaźników, łączący propagację wsteczną sztucz-nej sieci neuronowej (back-propagation artificial neural network – BPANN) oraz algorytm genetyczny (genetic algorithm – GA). Za pomocą wybranego modelu i wskaźników dokonano oceny Zielonej Produkcji w czterech firmach motoryzacyjnych. Wyniki wskazują, że chińskie przedsiębiorstwa motoryzacyjne mają jeszcze dużo do poprawy w kwestii satysfakcji klienta, zużycia zasobów, pracy społecznej, działań niskoemisyjnych, itp. Ko-nieczne jest zatem obranie strategii oraz gospodarki, które kładą nacisk na wymienione kwestie.

15

Selective adsorption of anionic polyacrylamide onto ultra-low ash coal and kaolinite

Zou W., Yu C., Sun C., Cao Y.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

738--753

EN

To study the selectivity of polyacrylamide in the selective floc flotation of fine coal, adsorption of anionic polyacrylamide (PAM A401) onto ultra-low ash coal and kaolinite was studied, including the adsorption thermodynamics, floc size distribution and wettability changes. The thermodynamics of the adsorption process at the low concentration of 0-16 mg/dm3 of PAM A401 were studied at different contact times, doses, temperatures and pH values. Thermodynamic parameters of ΔGo, ΔHo, ΔSo and Ea were evaluated to understand the nature of the adsorption process. The results indicated that PAM A401 was selectively adsorbed onto ultra-low ash coal rather than kaolinite. Physical adsorption was the predominant mechanism, and the adsorption of PAM A401 at 12 mg•dm-3 onto coal was 2.15-fold larger than the adsorption on kaolinite. After the adsorption of PAM A401, the lipophilic hydrophilic ratio (LHR) of coal decreased from 9.23 to 7.28, indicating that the coal became less hydrophobic than before. In contrast, the LHR of kaolinite increased from 1.44 to 1.65. Floc size measurements showed that the d10, d50 and d90 of coal flocculated by PAM A401 (at 12 mg/dm3, pH 6.5) were 3.18, 2.76 and 2.59-fold greater than the corresponding levels of these parameters for kaolinite flocs, respectively.

16

Flotation behavior of hard-to-separate and high-ash fine coal

Xing Y., Gui X., Liu J., Cao Y., Zhang Y., Li S.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

703--717

EN

The flotation behavior of hard-to-separate and high-ash fine coal was investigated using conventional flotation with constant power input. A new flotation process, based on energy input and distribution, was designed to lower the ash content of concentrate. The results obtained using Fourier transform infrared (FTIR) analysis show that the coal samples have good floatability because of many hydrophobic and few hydrophilic functional groups. Under a constant power input, a large number of ash-forming materials floated into a froth product at the start of flotation. Based on the Fuerstenau upgrading curves, it was determined that the 0.25-0.074 mm size fraction range showed the worst selectivity when compared with 0.50-0.25 mm and -0.074 mm size fractions. The desired concentrate with an ash content of 13.98%, 27.59% of ash recovery, and 80.01% combustible matter recovery could be obtained by transferring the excess energy of the flotation-conditioning stage to the pre-conditioning stage and increasing the power input step-by-step in the flotation-conditioning stage at equal total energy consumption.

17

Effect of intergrown particle liberation on difficult-to-separate coking coal flotation

Gui X., Liu J., Cao Y., Xing Y., Deng Y., Li S.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

279--294

EN

Flotation tests with intergrown particle liberation were conducted to explore a separation method of difficult-to-separate coking coal from the Tangshan Kailuan mine in China. The particle size distribution, density and coal petrography were investigated. The difficult-to-separate coking coal sample resulted in intergrown particles, such as non-liberated coal and rocks. Thus, intergrown coal particle liberation and re-separation tests were conducted. The results showed that grinding time had a great effect on the flotation performance. Grinding prompted coal to dissociate and improve the surface hydrophobic properties of minerals. However, heterogeneous fine silt covered the surface of coal particles when coal was ground too long. The inorganic mineral particles were over-ground and reduced the contact angle of coal. The results of coal rock dissociation and laboratory re-separation tests showed that clean coal combustible recovery increased through intergrown particle liberation and re-separation.

18

Adsorption mechanism of sodium oleate on titanium dioxide coated sensor surface using quartz crystal microbalance with dissipation

Fan G., Liu J., Cao Y., Feng L., Xu H.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

597--608

EN

Quartz Crystal Microbalance with Dissipation (QCM-D) was firstly applied to investigate the adsorption mechanism of sodium oleate on TiO2 coated sensor surface. The effects of pH value, sodium oleate concentration, and temperature on TiO2 coated sensor surface were evaluated systematically using the QCM-D technique. Zeta potential, surface tension, adsorption isotherms, and adsorption thermodynamics were employed to characterize the adsorption process. The results showed the advantages of QCM-D on the investigation of the adsorption process. Additionally, the electrostatic equilibrium adsorption data was well matched to the Langmuir isotherm. Based on the thermodynamic analysis, adsorption was a spontaneous and endothermic physisorption process.

19

Criteria for Sustainable Disposal of Sewage Sludge

Czechowska-Kosacka A., Cao Y., Pawłowski A.

Rocznik Ochrona Środowiska

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2015

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Tom 17, cz. 1

337--350

PL

Osady ściekowe są stanowią trwałe źródło związków fosforu i potasu niezbędnych do wzrostu biomasy. Od ich dostępności dla roślin zależy produkcja żywności dla stale wzrastającej liczby ludności. Do gleby dostarczane są związki fosforu i potasu w postaci soli pozyskiwanych jako kopaliny. Problem jednak stanowią szybko wyczerpujące się zasoby minerałów, z których pozyskiwane są wyżej wymienione pierwiastki do produkcji nawozów rolniczych. W przyszłości ich brak może pogorszyć jakość gleb, co zmniejszy skalę produkcji rolnej. Oznacza to, że podstawowy paradygmat zrównoważonego rozwoju mówiący o konieczności postępowania takiego, aby zapewnić niezbędne środki do życia obecnym pokoleniom, nie pozbawi przyszłych pokoleń możliwości zabezpieczenia ich potrzeb. Paradygmat ten nakazuje podjęcie wszelkich działań zdążających do ograniczania eksploatacji naturalnych ich zasobów. Poszukując innych źródeł zwrócono uwagę na osady ściekowe pochodzące z biologicznych oczyszczalni ścieków. Osady te zawierają związki fosforu i potasu, które po odpowiedniej obróbce mogą przyczynić się do spowolnienia zużycia naturalnych rezerw fosforu i potasu. Zastosowanie osadów ściekowych na uprawianej ziemi, może być korzystne pod warunkiem, że poziom zanieczyszczeń m.in. metalami ciężkimi nie przekracza dopuszczalnego poziomu. Biorąc pod uwagę ich możliwy negatywny wpływ na środowisko naturalne oraz surowe przepisy dotyczące zawartości zanieczyszczeń w osadach, metale ciężkie zostały uwzględnione w prawodawstwie omawianych regionów. Biorąc pod uwagę zalety wnikające z wykorzystania osadów ściekowych do nawożenia upraw i możliwych zagrożeń wynikających z obecności w osadach ściekowych niepożądanych zanieczyszczeń, wiele krajów wprowadziło surowe przepisy regulujące wykorzystanie osadów do nawożenia gleby. Biorąc pod uwagę przykład Europejskiej, USA, Polski i Chin można stwierdzić na podstawie analizy regulacji prawnych w tym zakresie, że stosowanie osadów ściekowych do nawożenia gleb jest w pełni kontrolowane zarówno w krajach rozwiniętych jak również w krajach rozwijających się.

20

The Ecological Amplitude of Acorus calamus Young Shoots Under Water Level Gradient

Cao Y., Guo Z., Yang Y., Wang G., Xie Z.

Polish Journal of Ecology

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2015

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Vol. 63, nr 4

585--592

EN

This paper analysed the influence of the gradient of water levels (-54–120 cm) on Acorus calamus (A. calamus) young shoots in terms of their growth characteristics (germination rate, basal stem, height and biomass), leaf characteristics (number, area and moisture content), chlorophyll (chl) fluorescence parameters (Fv/ Fm, ETR, qP and qN) and other indicators. Based on a Gaussian model, we determined and quantified the response relationship between A. calamus young shoots and water level. The results showed that the ecological amplitude of water level for A. calamus young shoots was -52.3−141.8 cm, and the optimum range was -3.5−69.3 cm; a variety of indicators suggested that the optimum depth for A. calamus young shoots was from18.8 cm to 49.6 cm. The A. calamus seedling growth characteristics which were sensitive to changes in the water level were the germination rate and biomass. The germination rate was more sensitive to the submergence water depth, but the biomass was obviously influenced by the groundwater depth. Therefore, the A. calamus could be a suitable species for ecological restoration of land/inland water ecotones in lakes, rivers and reservoirs.