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1

Determination of coumarin-3-carboxylic acid in the liver and heart tissue of Sprague-Dawley rats after intragastric administration of extractive of leaves of F. virens var. sublanceolata by HPLC

Xiang Yujie, Chuahe Bahetibieke, Zhang Jing, Li Jiansha, Jiang Xinhui

Acta Chromatographica

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2024

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Vol. 36, no. 1

1--6

EN

The study was aimed to validate and optimize high performance liquid chromatographic (HPLC) method for the determination of coumarin-3-carboxylic acid (C3A) in the heart and liver issue of Sprague-Dawley (SD) rats after intragastric administration of extractive of leaves of Ficus virens var sublanceolata. And simple ADME and target prediction analyses were performed for C3A. Ethyl acetate was employed to precipitate protein with appropriate sensitivity and acceptable matrix effects. The satisfactory separation was developed on an ODS2 column (4.6 mm × 250 mm, 5 μm) by gradient elution with a methanol-acetic acid solution (pH = 3.0) as the mobile phase. The flow rate was 1.0 mL min⁻¹, the column temperature was maintained at 30 ± 2 °C, the injection volume was 20 μL, and the detection wavelength was set as 309 nm. The method was fully validated in terms of selectivity, linearity, accuracy, precision, extraction recovery and stability. The results of the ADME analysis found that C3A has excellent characteristics of drug-likeness, consistent with good bio-absorption. And the predicted 12 target protein belongs to the amine oxidoreductase and carbonic anhydrase target class. This method is simple, rapid, sensitive, and accurate for the determination of coumarin-3-carboxylic acid in the heart and liver tissue of SD rats.

2

Simulation of the peak flow reduction of small reservoirs. A case study of the Brown Bridge Pond, Michigan, USA

Zhang Jing, Guo Chen-lin, Xie Guang-Ming, Xing Bin

Environment Protection Engineering

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2023

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Vol. 49, nr 3

83--94

EN

Due to the high frequency and great damage of flood disasters, it is important to reduce the flood peak when it goes through the reservoir. A hydraulic model which integrates the implicit equation of water balance, water head-discharge carves, and water head-storage carves together, is proposed to simulate the flood peak reduction of a small reservoir. The proposed method was employed to simulate the flood peak reduction in the Brown Bridge Reservoir, Michigan, US. The results show that the proposed method can simulate the flood peak reduction in a small reservoir, and the Brown Bridge Dam can reduce the flood peak when hundred-year floods go through. When all gates or spillways are fully opened, the initial water head of the reservoir significantly influences the capacity of flood peak reduction. When the initial water head of the Brown Bridge Reservoir is 240.18 and 241.40 m, the hundred-year flood peak would be reduced to 23.11 m3/s and 25.85 m3/s, respectively. By optimizing the gates or spillways, the hundred-year flood peak could be reduced. When the initial water head of the reservoir is 241.40 and 240.18 m, the hundred-year flood peak would be reduced to 17.98 and 16.54 m3/s, respectively

3

Research on communication emitter identification based on semi-supervised dimensionality reduction in complex electromagnetic environment

Ge Wei, Qi Lin, Tong Lin, Zhu Jun, Zhang Jing, Zhao Dongyang, Li Ke

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 4

art. no. e145766

EN

The individual identification of communication emitters is a process of identifying different emitters based on the radio frequency fingerprint features extracted from the received signals. Due to the inherent non-linearity of the emitter power amplifier, the fingerprints provide distinguishing features for emitter identification. In this study, approximate entropy is introduced into variational mode decomposition, whose features performed in each mode which is decomposed from the reconstructed signal are extracted while the local minimum removal method is used to filter out the noise mode to improve SNR. We proposed a semi-supervised dimensionality reduction method named exponential semi-supervised discriminant analysis in order to reduce the high-dimensional feature vectors of the signals, and LightGBM is applied to build a classifier for communication emitter identification. The experimental results show that the method performs better than the state-of-the-art individual communication emitter identification technology for the steady signal data set of radio stations with the same plant, batch and model.

4

Energy distribution law of coal–rock combined body under confining pressure effect

Chen Guangbo, Zhang Jing, Li Yuan, Liu Fengxu, Li Tan, Zhang Guohua

Acta Geophysica

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2023

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Vol. 71, no. 4

1831--1843

EN

Coal measure strata are composed of many kinds of rock layers with different properties, and the energy accumulation ability of each rock layer is different, which causes the uneven distribution of energy. In order to explore the accumulation layer of rock burst energy in coal–rock system, based on the structural characteristics and mechanical properties of coal and rock, the mechanical model of coal–rock combined body was constructed, and the calculation formula of energy distribution of coal–rock combined body was deduced. The axial compression tests of coal–rock combined body under five confining pressures (0, 5, 10, 15 and 20 MPa) were designed and carried out. The results show that: 1) Under five confining pressures, the average compressive strength of the specimens was 18.74 MPa, 20.75 MPa, 24.68 MPa, 28.02 MPa and 32.05 MPa, respectively. With the increase in confining pressure, the compressive strength also increased linearly; 2) Under the five confining pressures, the pre-peak accumulated energy of the specimens was 0.106 kJ, 0.244 kJ, 0.591 kJ, 0.758 kJ and 1.602 kJ. With the continuous increase in the confining pressure, the pre-peak accumulated energy increased exponentially; 3) With the increase in confining pressure, the coal component accumulation energy increased exponentially, followed by 0.069 kJ, 0.182 kJ, 0.440 kJ, 0.630 kJ and 1.419 kJ, and the proportion of coal component accumulation energy was 65.14%, 71.63%, 76.72%, 82.89% and 87.07%, respectively, which were all greater than 50%. Combined bodies accumulated more energy under loading conditions, most of which were accumulated on coal components, and coal components were the main carriers of energy accumulation, which played a leading role in the destruction of combined bodies; 4) The energy distribution test method was discussed and analyzed. The energy distribution test method of coal–rock combined body based on single specimen method could effectively avoid the influence of size effect and coal–rock individual difference on energy accumulation. At the same time, the test time was shortened, the test workload was reduced, and the calculation accuracy was improved; 5) The rationality and reliability of the two methods for direct and indirect determination of coal–rock component energy were demonstrated. The error rates of the two methods were 2.936%, 1.846%, 3.125%, 3.412% and 0.862%, which were less than 5%. The error had little effect on the test results. The research results have reference significance for exploring the key strata of rock burst energy accumulation and the precise prevention and control of rock burst.

5

The influences of source intensity and meteorological factors on sulfur dioxide and nitrogen oxides based on the path analysis mode

Guo Chen-Lin, Zhang Jing, Zhou Qian Shuang, Ma Yong

Environment Protection Engineering

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2022

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Vol. 48, nr 4

51--65

EN

With rapid economic development and industrialization, air pollution is becoming a critical global issue affecting health. Sulfur dioxide and nitrogen oxides are the major contributors to acid rain and the key indicators for evaluating atmospheric pollution. And source intensity and meteorological factors are the main ways to influence the concentrations of sulfur dioxide and nitrogen oxides. Thus, to investigate the specific effects of source intensity, temperature, humidity, wind speed and atmospheric pressure on SO2 and NOx, the path analysis method was used for the model. The results showed that Source intensity significantly affects the concentrations of SO2and NO2. For both NO2 and SO2, the source intensity accounted for around 40%. Meteorological factors have very limited effects on the concentrations of SO2and NO2. The effects of the meteorological factors on air pollutants are specific as differences in material properties. Humidity significantly affects the concentration of SO2while temperature, humidity and wind speed have significantly affected the concentration of NO2.

6

Simulation of the migration path of the maximum pollutants' concentration. Case study of the tailing pond, southwest China

Zhang Jing, Ma Yong, Xing Bing, Zhang Jian-Min, Ren Yu-Feng, Liang Yue

Environment Protection Engineering

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2022

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Vol. 48, nr 2

59--72

EN

Following China's economic development, lots of tailing deposits have become potential pollution sources, and their leaching would release the trace elements into the natural environment. The leakage rate model and the solute transport models of groundwater are coupled to investigate the effects of the tailing ponds on groundwater. It indicates that the anti-seepage layer is a necessary and important component of the tailing ponds, which could protect the soil or groundwater to be polluted by wastewater. Under three scenarios (scenario A - ideal conditions, scenario B - the worst conditions, and scenario C), the proportions of maximum concentration to source concentration are 1.2, 94.6, and 19.1%, respectively. Under the worst states of anti-seepage layers, the pollution areas after 730, 1800, 3807 and 7300 days were 130 500, 313 200, 523 800, and 729 000 m2, respectively. Compared with Scenario B, the pollution areas of Scenario C after 1800, 3807, and 7300 days were cut by 52.97, 74.55, and 81.73, respectively. Given important anti-seepage layers, the tracking monitor system is necessary and important to discover whether the groundwater was contaminated in time.

7

Improvement of leaching efficiency of cathode material of spent LiNixCoy MnzO2 lithium-ion battery by the in-situ thermal reduction

Lu Qichang, Jiang Haidi, Xie Weining, Zhang Guangwen, He Yaqun, Duan Chenlong, Zhang Jing, Yu Zhaoyi

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 2

70--82

EN

Green cars and electronic products consume lots of lithium-ion batteries (LIBs), and massive spent LIBs are yielded due to performance degradation. This paper provides an economical and environmentally friendly approach to recover valuable metals from cathode materials of the spent LIBs. It combines the in-situ thermal reduction (self-reduction by polyvinylidene fluoride (PVDF) and residual electrolyte in cathode material) and sulfuric acid leaching. Elements of high valent are reduced by the binder (PVDF) and the residual electrolyte on the surface of NCM(LiNixCoyMn1-x-yyO2) material at high temperatures. Moreover, the changes in substance type, element valency, and contents of cathode materials reduced with various terminal temperatures and retention time are analyzed by Xray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Results show that the optimal terminal temperature for in-situ thermal reduction is 600 °C, and the optimum retention time is 120 min. Under the best in-situ thermal reduction conditions, the results from XRD confirm that part of Ni2+ is converted to simple substance Ni, Co3+ is reduced to Co, and Mn4+ is reduced to Mn2+ and elemental Mn, which are confirmed by XRD. Analyzed results by XPS indicate that the content of Ni2+ decreases to 67.05%, and Co3+ is completely reduced to Co. Mn4+ is reduced to 91.41% of Mn2+ and 8.59% of simple substance Mn. In-situ thermal reduction benefits the leaching processes of cathode materials. The leaching efficiencies of Ni, Co, and Mn increase from 53.39%, 51.95%, and 0.71% to 99.04%, 96.98%, and 97.52%, respectively.

8

Transmission stability of chirped dark vector quasi-solitons in birefringent fiber system with nonlinear gain

Xiao Yan, Zhang Jing, He Qi

Optica Applicata

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2021

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Vol. 51, nr 1

51--58

EN

In this article, we consider the coupled Ginzburg–Landau equation with variable coefficients including the nonlinear gain and obtain the exact solutions of chirped dark vector quasi-solitons via the ansatz method. Next, the propagation of chirped dark vector quasi-solitons is discussed to verify whether they can be transmitted stably in the birefringent optical fiber system. The numerical simulation shows that this can be achieved. We deeply add the small perturbation to the transmission of dark vector quasi-solitons to make the results above more general. The results further prove the correctness of our solutions.

9

Seasonal Changes of Soil Nitrogen Mineralization Along Restoration Gradient of Sandy Grassland, Northern China

Lv Peng, Zuo Xiaoan, Sun Shanshan, Zhang Jing, Zhao Shenglong, Hu Ya

Polish Journal of Ecology

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2020

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Vol. 68, nr 4

283--295

EN

Soil nitrogen mineralization strongly affects N availability, thus impacting the primary productivity in ecosystems. The seasonal environmental changes affect soil mineralization in restored sandy grasslands such as a studied mobile dune (MD), a semi-fixed dune (SFD), a fixed dune (FD) and a grassland (G). During the growing season, we examined the association of soil N mineralization rate with vegetation characteristics, soil properties and climatic factors through the multivariate stepwise regression model. The vegetation cover, species diversity, above- and belowground biomass, soil carbon, nitrogen, soil water content (SWC), pH, electrical conductivity, very fine sand, clay and silt fractions increased during sandy grassland restoration. The NH4+-N concentration in MD and SFD was higher than that in FD and G, while NO3--N and inorganic N concentration showed a reverse trend. The NH4+N, NO3--N and inorganic N concentrations in MD, SFD and FD reached to the highest values in June, while in G they were highest in May. The net mineralization and nitrification rates increased with sandy grassland restoration; both of these rates were much greater in June than in other months at all sites. Regression analysis showed that the NO3--N concentration, SWC, pH of the soil and precipitation could explain 75% of the total variation in net nitrification rate, and the NO3--N concentration and precipitation could explain 59% of the total variation in the net mineralization rate. These results illustrate that the sandy grassland restoration can enhance the soil N availability, with soil N mineralization mainly determined by the changes of the NO3--N concentration and precipitation.

10

Influence of Branch Death on Leaf Nutrient Status and Stoichiometry of Wild Apple Trees (Malus sieversii) in the Western Tianshan Mountains, China

Tao Ye, Nuerhailati Maziyirea, Zhang Yuan-Ming, Zhang Jing, Yin Ben-Feng, Zhou Xiao-Bing

Polish Journal of Ecology

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2020

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Vol. 68, nr 4

296--312

EN

The wild apple tree Malus sieversii is a tertiary relict species and a key ancestor of the commonly cultivated apple trees today. In recent years, many M. sieversii individuals have died or have severe dead branches. Whether branch death would lead to the change in nutrient stoichiometry of M. sieversii remains unclear. In this study, the nitrogen (N), phosphorous (P), and potassium (K) stoichiometric traits of M. sieversii individual trees with different proportion of dead branches divided into three classes (Class I [< 20%], Class II [40-60%], and Class III [> 80%]) during annual growth period, elemental scaling relations, and the possible influencing factors were systematically analysed. Leaf N, P, and K decreased during growing season, and N and P did not show significant differences among the three classes; however, the Class III wild apple trees had the lowest K contents in both photosynthetic and reproductive organs. Flowers had higher P and K contents than leaves, whereas fruits had low N content. The growth of M. sieversii was always limited by N due to low N:P ratio and N resorption efficiency. The scaling exponents of leaf N-P, N-K, or P-K among the three classes did not show any significant differences, revealing an inherent property of M. sieversii. Most soil variables showed weak correlations with leaf nutrient parameters (except for K). Precipitation and relative humidity, rather than temperature, showed significantly positive effects on leaf nutrients. These findings suggest that increasing water input and plant K content may be conducive to enhance the resistance and recovery ability of diseased wild apple trees.

11

Humped Relationship between Herbaceous Species Richness and Biomass Reveals a Potential for Increasing Productivity in a Temperate Desert in Central Asia

Tao Ye, Zhou Xiao-Bing, Zhang Jing, Yin Ben-Feng, Wu Nan, Zhang Yuan-Ming

Polish Journal of Ecology

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2020

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Vol. 68, nr 1

67--83

EN

Species richness-biomass relationship has become a primary focus in plant community ecology. The most commonly reported pattern of species richness and biomass is the humped relationship with a peak in richness at moderate biomass, although negative, positive, or no relationships exited in some cases. However, the richness-biomass relationship in the temperate deserts of Central Asia, where herbaceous species with different life forms are abundant, remains unclear. In this study, 21-214 plots with herbaceous richness and aboveground biomass for each of four plot sizes (0.25, 25, 100, and 400 m2) were surveyed in early summer and early autumn in the Gurbantunggut Desert, China. Linear and quadratic regressions were employed to examine the richness-biomass relationship and the location of the richness peak. Significantly unimodal species richness-biomass relationships were observed in all plot sizes and seasons (except for 0.25 m2 plot in summer). In most cases (9/11), the biomass at the richness peak was higher than half of the biomass range. Meanwhile, the percent of sampling plots where the biomass was less than the peak was considerably greater than 50% (72.7 to 100%) in all cases, and nine of them were more than 95%, indicating strong interspecific coexistence and weak interspecific competition. In conclusion, under the background of increasing precipitation and nitrogen deposition, the humped richness-biomass relationship and the high percent of sampling plots with low biomass jointly revealed a huge potential for increasing productivity, which is crucial for the carbon fixation and ecosystem stability in deserts of Central Asia.

12

Effects of monovalent and divalent ions in coal gasification brine on the froth entrainment and flotation kinetics of anthracite coal

Zheng Kaidi, Bu Xiangning, Zhou Shaoqi, Zhang Jing, Shao Huaizhi, Sha Jie, Xie Guangyuan

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 5

960--974

EN

Water plays a critical role in various stages of flotation, which brings a lot of pressure to the flotation processing plants resided in dry areas. In this regard, it will be of significance to explore the feasibility of using wastewater resources in mineral flotation. Coal gasification brine (CGB) that contains a high concentration of salts becomes the subject of interest of this study. In this study, a synthetic CGB solution, which was prepared by adding NaCl, MgCl2, and CaCl2 to ultrapure water based on the composition of salts in a real CGB, was used in the flotation of anthracite coal. The comparison results based on the first-order model showed that flotation in the presence of the synthetic CGB solution gave a higher flotation selectivity (SI =7.086) than that of flotation in ultrapure water (SI=3.545). Water recoveries and average bubble sizes in the froth showed that the addition of the three salt ions (Na+, Mg2+, and Ca2+) was conducive to diminishing the entrainment of gangue materials as a result of the reduction of water reporting to the froth. Additionally, the zeta potentials and induction time measurements indicated that only divalent ions of Ca2+ and Mg2+ significantly compressed the double electrical layer and enhanced the attachment between bubbles and coal particles according to DLVO theory, which was further confirmed by the calculation of interaction energy between coal and bubbles. The findings of the present work may promote the use of CGB as a potential water resource in coal flotation.

13

Plant Functional Trait Response to Habitat Change and Grazing in a Semiarid Grassland : Unravelling Species Turnover and Intraspecific Variation Effects

Zhang Jing, Zuo Xiaoan, Lv Peng, Zhao Shenglong, Zhao Xueyong

Polish Journal of Ecology

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2019

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Vol. 67, nr 1

62--74

EN

Plant community assembly is determined by species turnover and intraspecific trait variations (ITV) controlled by environment changes. However, little is known about how species turnover and ITV affect the responses of plant community to habitat changes and grazing disturbance in semiarid grasslands. Here, we measured five functional plant traits in four typical grassland habitats under fencing and grazing disturbance in a semiarid grassland, Northern China, including plant height, specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content (LNC) and leaf carbon: nitrogen ratio (C:N). We also calculated the community weighted means (CWM) and non-weighted means (CM) of all traits and examined the relative roles of species turnover and ITV in affecting the responses of community traits to habitat changes and grazing disturbance. Our results showed that the CWM and CM values of five functional traits differed with grassland habitat changes. As compared to other grasslands, the Stipa steppe had the higher plant height, the sandy grassland had the higher SLA and lower LDMC, and the meadow had the lower LNC and higher C:N. Grazing decreased plant height across grassland habitats, as well as decreased SLA and increased LDMC in meadow. The responses of all community-level traits to habitat changes were driven by species turnover, while the responses of phenotypic traits (height, SLA and LDMC) to grazing were determined by both species turnover and ITV. So, we argue that ITV should be considered when understanding plant community assembly under grazing disturbance regime in semiarid grasslands.