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1

Advanced oxidative decolorization of Red Cl-5B: effects of dye concentration, process optimization and reaction kinetics

100%

Khan H. , Ahmad N. , Yasar A. , Shahid R.

Polish Journal of Environmental Studies

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2010

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tom 19

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nr 1

83-92

EN

Process conditions (dye concentration, pH and oxidant dose) were optimized for UV, O₃, H₂O₂/UV, O₃/UV, H₂O₂/O₃, and H₂O₂/O₃/UV to treat Red Cl-5B dye of varying concentrations (100, 300, and 500 mg/L). Ozonation resulted in color removal of more than 90%, whereas H₂O₂/O3 showed no advantage over the O₃ alone. However, H₂O₂/UV was found to be very suitable as it gave almost 100% decolorization in a relatively short reaction time. Decolorization rate for all processes was reduced to half when the dye concentration was increased from 100 to 300 mg/l. Comparative study of rate constants revealed that H₂O₂/UV is four times faster than that of UV alone. On the other hand O₃/H₂O₂ is three to four times slower than O₃ alone.

2

Freshwater green algal biofouling of boats in the Kabul River, Pakistan

100%

Khuram I. , Ahmad N. , Jan S. , Barinova S.

Oceanological and Hydrobiological Studies

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2014

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tom Vol. 43, No. 4

329--336

EN

Freshwater green algal biofouling of boats refers to the accrual of freshwater green algae on boats immersed in water. The current research focused on the morphological characteristics of the isolates, species ecology, and the physicochemical properties of the water at the sampling sites. Two localities, Haji Zai and Sardaryab, were sampled at the Kabul River in the district of Charsadda, Pakistan. Freshwater green algae causing biofouling were isolated from the boats. A total of three genera: Cladophora, Rhizoclonium, and Spirogyra with fifteen species belonging to the families Cladophoraceae and Zygnemataceae were observed. Statistical analysis reveals significant stimulation of green algal species in the boats’ fouled communities by increases in water temperature, conductivity, and Total Suspended Solids (TSS). The algal growth at the Haji Zai site is suppressed by TDS in autumn (Pearson −0.56) and is stimulated by water temperature in spring (Pearson 0.44). At the Sardaryab site, algae were stimulated in spring by pH of water (Pearson 0.61), and suppressed by Total Dissolved Solids (TDS) in autumn (Pearson −0.43). Statistical analysis indicates that pH, conductivity, and temperature are the main factors determining the algal biofouling in the Kabul River.

3

Rapid plant regeneration and analysis of genetic fidelity in micropropagated plants of Vitex trifolia: an important medicinal plant

100%

Ahmad N. , Javed S. B. , Khan M. I. , Anis M.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 08

EN

An efficient in vitro regeneration protocol of a valuable medicinal plant, Vitex trifolia has been successfully established using nodal segments as explants. Three different cytokinins (BA, Kn, 2iP) and auxins (NAA, IAA, IBA) in different concentrations and combinations, evaluated as supplements to Murashige and Skoog’s medium showed to have a marked influence on the regeneration output. Among all the single cytokinin treatments MS medium supplemented with 5.0 μM BA produced the maximum number of shoots yielding 8.20 ± 0.37 shoots per explant with 4.8 ± 0.43 cm shoot length after 8 weeks of culture. Combined with low auxin concentrations, all the three cytokinins at their optimal concentrations synergistically enhanced the regeneration credentials. However, MS medium enriched with 5.0 μM BA and 0.5 μM NAA yielded the best possible regeneration in the species with a regeneration percentage of 97.33 ± 2.67 % and amounting to 16.80 ± 0.58 shoots per explant with 6.20 ± 0.25 cm mean shoot length at the end of 8 weeks in culture. Ex vitro rooting of in vitro derived microshoots was achieved by 20 min 500 μM IBA treatment followed by transfer to thermocol cups containing sterile soilrite. A 95 % plantlets survived acclimatization procedure to the field. Genetic conformity of the regenerated plants was established through RAPD. All the bands visualized on agarose gels were monomorphic with that of the donor plant indicating the clonal nature of the regenerants.

4

Integrated nutrient management for wheat by municipal solid waste manure in rice-wheat and cotton-wheat cropping systems

100%

Akram M. , Akram Qazi M. , Ahmad N.

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2007

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tom 16

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nr 4

495-503

EN

The effects of integrated nutrient management (INM) by municipal solid waste manure (MSWM) on wheat yield were studied in rice-wheat and cotton-wheat systems. Each site was used as an independent experimental unit. Two fertilizer doses (conventional and site-specific) were applied in each of three improved techniques: chemical fertilizers, and MSWM plus chemical fertilizers with and without pesticides/ herbicides. The results of three years field trials portrayed the role of INM with MSWM treatment by 9% increased wheat grain and straw yields over unique fertilizer application in cotton-wheat system only. However, INM technique helped in sustaining soil-test P status near to sufficiency levels during 3 years of experimentation in both systems.

5

Effects of different parameters on photocatalytic oxidation of slaughterhouse wastewater using TiO2 and silve-doped TiO2 nanoparticles

100%

Bukhari K. , Ahmad N. , Sheikh I. A. , Akram T. M.

Polish Journal of Environmental Studies

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2019

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tom 28

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nr 3

EN

Our study used a photocatalytic oxidation process for degrading slaughterhouse wastewater (SHWW). Characterization of the wastewater before and after treatment with TiO₂ and Ag-TiO₂ in terms of BOD, COD, and nitrogen was done. The effect of hydrogen peroxide, ozone, and various operating parameters such as catalyst dose, pH, and reaction time on the degradation efficiency of the process were also investigated. An increase in catalyst dose and reaction time increased process efficiency. However, process efficiency was decreased with elevating pH. The results also revealed that the type of catalyst and their operating parameters have significant influence on the oxidation of SHWW. Ag-TiO₂ -H₂O₂ catalyst under UV (400watt) irradiation was found to be best for the degradation of SHWW and resulted in 95% BOD, 87% COD, and 74% nitrogen removal.

6

Photocatalytic degradation of synthetic textile effluent by modified Sol-Gel, synthesized mobilized and immobilized TiO2, and Ag-doped TiO2

100%

Akram T. M. , Ahmad N. , Shaikh I. A.

Polish Journal of Environmental Studies

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2016

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tom 25

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nr 4

EN

Advanced oxidation processes (AOPs) have proven to be very effective for treating various hazardous organic pollutants in water. The present study uses a double-walled horizontal glass reactor (DHGR) to investigate heterogeneous UV/TiO2 (titanium dioxide) and UV/Ag-TiO2 (mobilized and immobilized) photocatalytic degradation of synthetic textile effluent (Remazol Red RGB) with UV (400W). The textile effluent was characterized in terms of pH, chemical oxygen demand (COD), and degree of decolorization (at 519 nm) before and after treatment. Optimum degradation results were obtained at pH3. We also found that with different catalysts and catalyst doses, the rate of degradation rises up to a maximum “critical” value. The electron scavenger was Ag-led to a faster degradation of synthetic textile effluent in the photocatalytic system. The photocatalytic degradation proved to be dependent on the effluents’ initial COD, catalyst dose, catalyst form, and pH of the medium. Results reveled that among different forms of catalysts, Ag-TiO2 (Mesh) and TiO2 (0.5 g) showed better COD percentage and ABS percentage removal at pH3 with initial concentrations of synthetic effluent 560mg/l under UV(400W) irradiation.

7

Freshwater green algal biofouling of boats in the Kabul River, Pakistan

100%

Khuram I. , Ahmad N. , Jan S. , Barinova S.

Oceanological and Hydrobiological Studies

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2014

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tom 43

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nr 4

8

Encapsulation of microcuttings for propagation and short-term preservation in Ruta graveolens L.: a plant with high medicinal value

100%

Ahmad N. , Faisal M. , Fatima N. , Anis M.

Acta Physiologiae Plantarum

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2012

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tom 34

|

nr 6

EN

Synthetic seeds technology is a potential tool for an efficient and cost-effective clonal propagation system. In the present study, synthetic seeds were produced by encapsulating nodal segments (synthetic or synseeds) of Ruta graveolens in calcium alginate gel. The best gel complex was achieved using 3 % sodium alginate and 100 mM Cal₂.2H₂O. Maximum conversion response of synthetic seeds into plantlets was obtained on MS medium supplemented with 10 µM 6-benzyladenine (BA) and 2.5 µM α-naphthalene acetic acid (NAA). Encapsulated nodal segments could be stored at low temperature (4 °C) up to 4 weeks with a survival frequency of 86.7 %. The regenerated shoots rooted on MS medium containing 0.5 µM indole-3-butyric acid (IBA). Well-developed plantlets with proper root and shoot system from encapsulated nodal segments were hardened off successfully with 90 % survival rate. The high frequency of plant re-growth (conversion) from alginate-coated nodal segments coupled with high viability percentage after 4 weeks of storage is highly encouraging for the exchange of R. graveolens genetic resources.

9

Disinfection of UASB-treated municipal wastewater by H2O2, UV, ozone, PAA, H2O2/sunlight, and advanced oxidation processes: regrowth potential of pathogens

88%

Rizvi H. , Ahmad N. , Yasar A. , Bukhari K. , Khan H.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 4

EN

Disinfection of anaerobically treated municipal wastewater was done using ozone, UV, H2O2, peracetic acid, and advanced oxidation processes (O3/H2O2, O3/UV, H2O2/UV, H2O2/sunlight). Ozone, UV irradiation, and H2O2 eliminated 99% of pathogens (total coliform, fecal coliform, and E. coli) at ozonation time of 20 min at the rate of 1000 mg/hr; UV irradiation time of 11 min and H2O2 dose of 336 mg/L. The use of combined systems (H2O2/sunlight) is especially promising due to the synergistic effect and cost efffectiveness. Regrowth of pathogens increased with increase in time and temperature (from 15 to 35ºC). The presence of nutrients and fluorescent light enhanced the rate of reactivation of pathogens.

10

Ozone for color and COD removal of raw and anaerobically biotreated combined industrial wastewater

88%

Yasar A. , Ahmad N. , Chaudhry M. N. , Rehman M. S. U. , Khan A. A. A.

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2007

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tom 16

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nr 2

EN

Ozonation was carried out for decolorization and COD removal of raw and anaerobically treated UASB (upflow anaerobic sludge blanket) combined industrial (mainly textile) effluent in a lab-scale bubble column reactor. Ozonation of anaerobic bioprocess effluent at a dose of 300 mg/h for 10 min resulted in 81% color and 75% COD removal (100 mgO3/80 mg COD) while for raw wastewater 25 min ozonation furnished 51% color and 67% COD removal (250 mgO₃/345 mg COD). Optimal process conditions for biotreated effluent (pH = 8 and temperature = 25°C) resulted in 100% color and 96% COD removal for 10 min ozonation (100 mgO₃/104 mg COD). Electrical energy comparison demonstrated that post ozonation required less electrical energy, 16 and 2.9 times as compared to pre ozonation.

11

Statistical Estimation and Mathematical Modelling of Tropospheric Radio Refractivity Based on Meteorological Data

75%

Alimgeer K. S. , Awais M. , Ijaz B. , Khan S. A. , Subhan F. , Ahmad N.

Metrology and Measurement Systems

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2018

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tom Vol. 25, nr 1

115--128

EN

To obtain optimal performance, estimation of radio refractivity is essential in planning and design of radio links/systems. The dependence of radio refractivity on different climatic parameters such as temperature, pressure, humidity and scale height is studied. The method proposed by International Telecommunication Union (ITU) is used in calculation of tropospheric radio refractivity. The main objective of this work is to formulate a mathematical equation/expression which can be used to predict/estimate the value of radio refractivity for an arbitrary day of any year, with a low error of estimation, in a local environment. Sensitivity of radio refractivity to temperature, pressure and humidity has been evaluated for a period of 5 years from 2008 to 2012, in a particular area under consideration. The results presented for tropospheric radio refractivity take into consideration both the location height and scale height parameters. The results are analysed in terms of statistical measures such as the moving averages, probability density function, monthly mean values, and their corresponding standard deviations. Finally, a mathematical model is formulated to calculate the radio refractivity for any day of a whole year. Reliability of error analysis in respect to accuracy is also shown. It was implemented in the industrial enterprise.

12

The Site Preference Analysis and Ordering Characteristics of Ternary Cu0.5(Zn1–xMx)0.5 (M = Transition Metals) Alloys

75%

Ahmad N. , Ziya A. B. , Atiq S. , Saifullah K. , Hashim M. , Saleem M.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 3

1531--1535

EN

The site preference of some transition metals during B2-type ordering has been investigated in the ternary Cu0.5 (Zn1-x Mx )0.5 alloys with M = Ti, V, Ag, Au, Cr, Mn, Fe, Co, Ni, Nb, Mo, Hf, Ta, W, Re or Pt (x ≤ 0.01). The statistic-o-thermodynamical theory combined with the electronic theory of alloys has been used to calculate the partial ordering energies, partial short range order parameters and the order-disorder transformation temperatures. The values of partial short range order parameters have been used to determine the site preference of the metal M. The analysis shows that the metals M can be divided into two groups with regard to lattice site occupancy. One group comprising of Cr, Mn, Fe, Co, Ni, Nb, Mo, Hf, Ta, W, Re or Pt was found to prefer Zn sublattice sites, while the second group of Ti, V, Ag or Au atoms prefer Cu sublattice sites. It is found that order-disorder transformation temperature and the site preference of metal M both depend strongly on the partial ordering energies and ternary alloying addition of metal M.

13

The Site Preference Analysis and Ordering Characteristics of Ternary Cu0.5(Zn1–xMx)0.5 (M = Transition Metals) Alloys

75%

Ahmad N. , Ziya A. B. , Atiq S. , Saifullah K. , Hashim M. , Saleem M.

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14

Ecological assessment of water quality in the Kabul River, Pakistan, using statistical methods

75%

Khuram I. , Barinova S. , Ahmad N. , Ullah A. , Ud Din S. , Jan S. , Hamayun M.

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tom Vol. 46, No. 2

140--153

EN

We identified 209 species of algae and cyanobacteria at 4 sites in the Kabul River. Green algae, diatoms, and charophytes dominated in the river, which reflects regional features of agricultural activity. Species richness and algal abundance increased down the river. The Water Quality Index characterizes the quality of water down the river as medium to bad. The index of saprobity S reflects Class III water quality. The Water Ecosystem Sustainability Index (WESI) shows contamination with nutrients. According to the River Pollution Index (RPI), waters in the river have low alkalinity and low salinity, and are contaminated with nutrients. Pearson coefficients showed that water temperature plays a major role in the total species richness distribution (0.93*) and in the green algae distribution (0.89*), while cyanobacteria were stimulated also by water salinity (0.91*). Stepwise regression analysis indicated water temperature as the major regional factor that determines riverine algal diversity. Surface plots and Canonical Correspondence Analysis (CCA) showed that salinity, nitrates, temperature, and Biochemical Oxygen Demand (BOD) can be defined as major factors affecting algal diversity. Dendrites mark the upper site of the Warsak Dam as the source of the community species diversity. Bioindication methods can give relevant and stable results of water quality and self-purification assessment that can be employed to monitor the regional water quality.

15

Effect of Weave Structure on Thermo-Physiological Properties of Cotton Fabrics

75%

Ahmad S. , Ahmad F. , Afzal A. , Rasheed R. , Mohsin M. , Ahmad N.

Autex Research Journal

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2015

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tom Vol. 15, no. 1

30--34

EN

This paper aims to investigate the relationship between fabric weave structure and its comfort properties. The two basic weave structures and four derivatives for each selected weave structure were studied. Comfort properties, porosity, air permeability and thermal resistance of all the fabric samples were determined. In our research the 1/1 plain weave structure showed the highest thermal resistance making it suitable for cold climatic conditions. The 2/2 matt weave depicted the lowest thermal resistance which makes it appropriate for hot climatic conditions.

16

The synergistic effects of sucrose and plant growth regulators on morphogenesis and evaluation of antioxidant activities in regenerated tissues of Caralluma tuberculata

63%

Zamir R. , Khalil S. A. , Ahmad N. , Rab A. , Shah S. T. , Jabeen N. , Ali S. , Ali M.

Acta Physiologiae Plantarum

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2016

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tom 38

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nr 08

17

Characterizing microbial populations in petroleum-contaminated soils of Swat district, Pakistan

63%

Uddin M. N. , Ali M. , Muhammad M. , Farooq M. , Ahmad N. , Jamil J. , Kalsoom J. J. , Adnan M. , Shah N. , Khan A.

Polish Journal of Environmental Studies

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2016

|

tom 25

|

nr 4

EN

Soil samples from petroleum-contaminated soil were collected from 25 different petroleum filling stations and automobile workshops in the district of Swat, Khyber Pakhtunkhawa, Pakistan. A total of seven bacterial genera were isolated. All of the isolates were Gram-positive bacteria. The genera identified by the culture and cell morphological characteristics were: Bacillus, Streptococcus, Staphylococcus, Micrococcus, Corynebacterium Arthrobacter, and Streptomyces. Lipolytic and saline activities of the selected isolates were studied. Among the isolates, Arthrobacter, Staphylococcus, Bacillus, Micrococcus, Corynebacterium, and Streptomyces produced lipase enzymes, while no lipase was produced by Streptococcus. Dense growth of Bacillus and Streptococcus was observed at 1% NaCl. Dense growth of Streptomyces was observed at strength of 2% NaCl. At 3% NaCl concentration, dense growth of Staphylococcus, Micrococcus, Corynebacterium, and Arthrobacter was observed, indicating that they were moderately halotolerent. In our study, Bacillus, Arthrobacter, and Streptomyces showed optimum growth at pH 8.0, and Streptococcus, Staphylococcus, and Micrococcus showed optimum growth at pH 7.0. Only Corynebacterium showed optimum growth at pH 9.0, indicating that it is tolerant of higher pH conditions.

18

Growth, yield and nutritional performance of sweet sorghum and legumes in sole and intercropping influenced by type of legume, nitrogen level and air quality

63%

Arshad M. , Nawaz R. , Ahmad S. , Shah G. A. , Faiz F. , Ahmad N. , Irshad M. A. , Ranamukhaarachchi S. L.

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nr 1