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Journal of Rare Earths 2024年第10期42卷 1995-2002页

作者： Minakshi Koundal chhaya sharma A.K.Singh Department of Applied Science and Engineering Indian Institute of Technology RoorkeeSaharanpur Campus Department of Pulp and Paper Technology Indian Institute of Technology Roorkee Saharanpur Campus

Cerium tartrate（CeTar）,produced in this study by precipitating cerium nitrate with potassium sodium tartrate（KNaTar）,was examined as a corrosion *** loss tests show inhibition efficiency of 71.7% with Ce（NO3）3and 88.7% with CeTar inhibitor for one-month exposure to mild steel in 7 g/L NaCl *** inhibition efficiency drops to 28.6% with the fo rmer and remains around 8 7% with the latter inhibitor after six months of *** results from electrochemical testing indicate that the inhibition efficiency decreases by adding cerium ***,the cerium tartrate inhibitor demonstrates a nearly constant inhibition efficiency for up to 30 d,i.e.,≈90%.Electrochemical impedance spectroscopy（EIS） performed in these cases shows the following results:（ⅰ） with cerium nitrate,a film of iron and cerium oxide,which on prolonged exposure diminishes,and（ⅱ） with cerium tartrate,the formation of a bimetallic film（Fe-tartrate-Ce） and a mixture of cerium hydroxide and iro n oxide that protects steel for a longer *** inferences are based on the analyses of scanning electron microscopy/energydispersive X-ray analysis（SEM/EDAX）,X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR）,X-ray photoelectron（XPS）,and Raman spectroscopy results.

关键词： Cerium nitrate Cerium tartrate Corrosion inhibition Inhibitor film characterization Mild steel Rare earths

Detection of Chlorophenolic Compounds in Bleaching Effluents of Chemical Pulps

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中国造纸 2008年第5期27卷 35-40页

作者： chhaya sharma S. Mohanty S. Kumar N.J. Rao Department of Paper Technology IIT-Roorkee India Gas Authority of India Ltd. Calcutta India JP Institute Gunna India

Laboratory bleaching effluents from the chlorination and caustic extraction stages of mixed wood kraft pulp processing have been analysed both qualitatively and quantitatively for various chlorophenolics by using GC.A number of chlorinated derivaties of phenols,catechols,guaiacols and syringaldehydes have been detected and their concentrations are *** results are compared with that of different agriculture residue/hardwood pulps,which were reported in *** concentrations of various compounds detected have also been compared with their reported 96LC50 values.

关键词：化学纸浆漂白方法制造方法造纸技术

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Gas Chromatography Analysis of Resin and Fatty Acids from Laboratory Generated Bleach Plant Effluents

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中国造纸 2007年第5期26卷 29-33页

作者： chhaya sharma S. Mohanty S. Kumar N.J. Rao Department of Paper Technology llT-Roorkeelndia Gas Authority of India Ltd. Calcutta India JP Institute Gunna India

Laboratory generated spent bleached liquor from the chlorination, caustic extraction stage of mixed wood kraft pulp processing has been analyzed both qualitatively and quantitatively for various resin & fatty acids by using GC. A number of resin acids, saturated and unsaturated fatty acids, chloro fatty and resin acid have been detected and their concentrations are estimated. The results are compared with results on different agriculture residue/hardwood pulps, which were reported earlier. The concentrations of various compounds detected have also been compared with their reported LC50 values.

关键词：气相色谱分析脂肪酸树脂酸漂白废液

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Remediation of Pulp and Paper Industry Effluent Using Electrocoagulation Process

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Journal of Water Resource and Protection 2019年第3期11卷 296-310页

作者： Dushyant Kumar chhaya sharma Environmental Research Laboratory Department of Paper Technology Indian Institute of Technology Roorkee Saharanpur Campus Saharanpur India

Electrocoagulation of pulp and paper industry effluent with SS-304 electrode has been carried out under varying process variable such as pH, current density, time and dose of electrolyte to find out the optimum conditions. Maximum reduction efficiency of Chemical Oxygen Demand (COD) 82% and color more than 99% from pulp and paper industry wastewater at the following conditions pH = 7, current density = 24.80 mA/cm2 time = 40 min and dose of electrolytes = 1.0 g/L. Moreover, effects of electrolytes dosage on electricity consumption were observed and found to be that NaCl is better in comparison of Na2SO4 in respect of lower down the electricity consumption. But application of NaCl causes the formation of hazardous compounds as secondary pollutants within treated water. Therefore, Na2SO4 could be a potent replacement of NaCl to enhance the conductivity of paper industry effluent treated by EC process. The treated water has been compared with standard of Central Pollution control board (CPCB) and World Health organization, and found to be suitable for the reuse in irrigation.

关键词： Pulp Paper Industry Electrocoagulation Treatment Wastewater Reuse Chemical Oxygen Demand Color

Bacteria in Indian Food Packaging Papers and Paperboards with Various Contents of Pulp Fiber

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Food and Nutrition Sciences 2019年第4期10卷 349-357页

作者： Swati Sood chhaya sharma Environmental Research Laboratory Department of Paper Technology Indian Institute of Technology Roorkee Saharanpur Campus Saharanpur India

The food packaging industry generally uses papers and paperboards (PPBs) especially for disposable products. According to the Framework Regulation (EC) No. 1935/2004 of the European Union, no transfer of contamination should occur from food packaging material to the food items. The aim of this study was to determine the presence, numbers, source and different kinds of bacteria present in food packaging PPBs with various contents of pulp fiber. The samples were randomly collected from popular confectioners and fast food restaurants in Saharanpur, India. The results indicated the presence of bacteria in all the samples, ranging from 1.3 × 102 to 6.1 × 103 cfu/g. Most of the samples contained bacteria in more than the permitted concentration of 2.5 × 102 cfu/g as set by Food and Drug Administration (FDA). The detected bacteria were from genera Bacillacea, Staphylococcus and Pseudomonas. According to the FDA declaration, pathogenic bacteria such as B. cereus and S. aureus have been associated with food borne diseases (FBD). Some contaminants in food packaging PPBs were found to be B. subtilis and P. aeroginosa, which produce enzymes like peroxidases and lipoxygenases that are odor generating enzymes.

关键词： Bacteria Odor Health Safety Food Packaging Papers and Paperboards (PPBs) Pulp Fiber

Levels of Selected Heavy Metals in Food Packaging Papers and Paperboards Used in India

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Journal of Environmental Protection 2019年第3期10卷 360-368页

作者： Swati Sood chhaya sharma Environmental Research Laboratory Department of Paper Technology Indian Institute of Technology Roorkee Saharanpur Campus Saharanpur India

In the present study, the varieties of papers and paperboards (PPBs) used in India for food packaging were qualitatively and quantitatively analyzed for the heavy metal contamination with the help of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry). Total 10 different types of food packaging PPBs were procured from local market and analyzed for 14 heavy metals (Al, As, B, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Te, Ti and V). Quantities of heavy metals in the samples were compared with permitted values published by the European Council. Heavy metals like Al, As, Ba, Cr, Co, Ni, Pb and V were observed in more than the permitted concentration in some of the samples. Heavy metals toxicity in food packaging material is a serious concern as the edible items get exposed to these metals and also generate volatile odorous compounds which considerably impact the quality of food and affect consumer's health.

关键词： Heavy Metals Odorous Compounds Food Packages Papers and Paperboards (PPBs) Health

Ecofriendly Remediation of Pulp and Paper Industry Wastewater by Electrocoagulation and Its Application in Agriculture

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American Journal of Plant Sciences 2018年第12期9卷 2462-2479页

作者： Dushyant Kumar Vivek Kumar Gaurav chhaya sharma Environmental Research Laboratory Department of Paper Technology Indian Institute of Technology Roorkee Saharanpur Campus Saharanpur India

In the present study pulp and paper industry effluent was treated with the help of aluminum electrode using electrocoagulation (EC) process with feasible sludge management. The influences of pH, time, current density and electrolytes dose were investigated and optimum conditions were established to reduce the maximum amount of Chemical Oxygen Demand (COD) and color. At optimum conditions 70% of COD and 98% of color were removed. Additionally, the behavior of electrolytes (NaCl and Na2SO4) was determined;it has shown that Na2SO4 results in the generation of less secondary pollutants than that NaCl and thereby could be used as better replacement in paper industries for electrocoagulation mediated treatment of wastewater. The residual amount of operational parameters in EC treated water was compared to the World Health Organization (WHO) and Central Pollution Control Board (CPCB) of India. It was found to be safe for utilization in irrigation. Furthermore, sludge produced during the EC process has been analyzed for physicochemical characteristics. To understand the physical and elemental phases of sludge, the analytical technique such as field emission electron microscope coupled with energy dispersive spectroscopy has been used to find out the possible management alternative.

关键词： Pulp and Paper Wastewater Electrocoagulation Reuse Irrigation Sustainable Sludge Management

Assessment of Metal Accumulation in the Vegetables and Associated Health Risk in the Upper-Most Ganga-Yamuna Doab Region, India

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American Journal of Plant Sciences 2018年第12期9卷 2347-2358页

作者： Vivek Kumar Gaurav Dushyant Kumar chhaya sharma Environmental Research Laboratory Department of Paper Technology Indian Institute of Technology Roorkee Roorkee India

The present study indicates the status of metal contamination in the vegetables/crops grown in the upper most Ganga-Yamuna doab region of India and associated health risk. Commonly grown vegetables and crops were sampled and analyzed for the metal contamination. Maximum concentration (mg/kg) of Cd and Cr, was observed in Radish (7.6) and Cabbage (56.24) respectively, whereas maximum concentration of Pb, Ni and Zn was observed in the edible parts of Mustard plant (95.4, 58.6, 756.43 respectively). Bio-concentration factor (BCF) value indicated the transfer level of metal from soil to crop;indicated high transfer value of Cd in Radish followed by cabbage and spinach. Considerably high BCF value was observed in the Mustard (8.13), Cabbage (4.18) and radish (3.07) for Zn contamination. Estimated daily intake (EDI) and Hazard quotient (HQ) or Non-carcinogenic health risk was calculated using the USEPA method. The result revealed that the metal intake and associated health risk were considerably high in the children population in comparison to the adult population.

关键词： Heavy Metal Bio-Concentration Factor Estimated Daily Intake Health Risk Hazard Quotient

Numerical simulation of square shaped particle sedimentation

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Particuology 2024年第1期84卷 107-116页

作者： Govind sharma Bahni Ray Department of Mechanical Engineering Indian Institute of Technology DelhiHauz KhasNew Delhi110016India

Direct numerical simulations of square particle sedimentation in a viscous incompressible fluid are presented to examine the effects of sharp edges for various particle-to-fluid density ratios and different initial inclination *** settling process exhibits four different motion regimes;non-oscillatory,non-uniform centered oscillatory,uniform off-centered oscillatory,and non-uniform off-centered(irregular)*** moderate density ratios,we observe that the rotational motion of settling square particle varies with the initial inclination *** employ Dynamic Time Warping and Fast Fourier Transform to analyze translational and angular *** systems are described using phase-space plots,and a chaotic phenomenon is observed at a higher density ratio.

关键词： Sedimentation Distributed Lagrangian multiplier Phase synchronization Oscillations

Sequential decay analysis of^(235)U(n^(th),f)reaction using fragmentation approach

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Chinese Physics C 2024年第6期48卷 145-154页

作者： Nitin sharma Ashutosh Kaushik Manoj K.sharma School of Physics and Materials Science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

Numerous experimental and theoretical observations have concluded that the probability of the three fragment emission(ternary fission)or binary fission increases when one proceeds towards the heavy mass region of nuclear periodic *** factors affect fragment emission,such as the shell effect,deformation,orientation,and fissility *** and ternary fissions are observed for both ground and excited states of the *** collinear cluster tripartition(CCT)channel of the^(235)U(n^(th),f)reaction is studied,and we observe that the CCT may be a sequential or simultaneous emission *** date,different approaches have been introduced to study the CCT process as a simultaneous or sequential process,but the decay dynamics of these modes have not been not fully *** the three fragments of the sequential process and exploring their related dynamics using an excitation energy dependent approach would be of further ***,in this study,we investigate the sequential decay mechanism of the^(235)U(n^(th),f)reaction using quantum mechanical fragmentation theory(QMFT).The decay mechanism is considered in two steps,where initially,the nucleus splits into an asymmetric *** the second step,the heavy fragment obtained in the first step divides into two *** I analysis is conducted by calculating the fragmentation potential and preformation probability for the spherical and deformed choices of the decaying *** most probable fragment combination of stage I are identified with respect to the dips in the fragmentation structure and the corresponding maxima of the preformation probability(P0).The light fragments of the identified decay channels(obtained in step I)agree closely with the experimentally observed *** excitation energy of the decay channel is calculated using an iteration *** excitation energy is shared using an excitation energy dependent level density *** obtained excitation

关键词： fission cluster radioactivity ternary fission spontaneous fission cluster model total kinetic energy preformation probability

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