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Extraction and Enrichment of Copper by Liquid Emulsion Membrane Using LIX 664N

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j.urnal of Environmental Protection 2014年第17期5卷 1611-1617页

作者： Rashmi Kumar dahyalal j. shah Krishna Kant Tiwari D. j. Sanghvi College of Engineering Mumbai India Mukesh Patel School of Technology Management & Engineering (NMIMS) Mumbai India j.ypee University of Engineering and Technology (Guna) Madhya Pradesh India

Process intensification using liquid emulsion membranes (LEMs) for extraction of copper has been studied in this work. In LEM process the extraction and stripping processes are combined in one stage. The solubility of the solute or the chemical affinity between the solute and carrier reagent in the membrane results in the separation of the solute from the feed mixture. In this work the membrane phase comprised of LIX 664N as the extractant dissolved in kerosene and Span 80 as surfactant. The stripping phase was sulfuric acid with 180 g/l concentration and feed phase had copper concentration of 3.5 g/l. Effect of various process parameters such as batch contact time, speed of agitation, W:O ratio and treat ratio has been experimentally investigated to get better insight of the process. The maximum enrichment of copper in the internal phase obtained was 11.6 times with batch contact time of 10 minutes, agitation speed of 300 rpm and treat ratio of 6:1.

关键词： Extraction Enrichment Liquid Emulsion Membranes LIX 664N Copper

Separation of Copper and Nickel by Solvent Extraction Using LIX 664N

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j.urnal of Environmental Protection 2013年第4期4卷 315-318页

作者： Rashmi Kumar dahyalal j. shah Krishna Kant Tiwari D. j. Sanghvi College of Engineering Mumbai India j.ypee University of Engineering and Technology (j.ET) Madhya Pradesh India Mukesh Patel School of Technology Management & Engineering (NMIMS) Mumbai India

Separation of copper and nickel by liquid-liquid extraction from aqueous solutions was studied using LIX 664N in kerosene as solvent. Both metals were taken in their sulfate form and ratio of copper to nickel in feed solutions was maintained as 10:1. LIX 664N concentration in kerosene was varied from 10% to 40% (v/v) and its effect was studied on percent extraction of copper and nickel for organic to aqueous (O:A) phase ratio of 2:1 at pH 2. Experimental results showed that at pH 2, copper was selectively extracted from its mixture with nickel. Selectivity for copper extraction was as high as 6000 with 40% LIX 664N. Calculations using extraction isotherm indicate almost complete recovery of copper in two stages with O:A ratio of 1:1 and in one stage with O:A ratio of 2:1. After extraction of copper, the pH of raffinate containing nickel was adj.sted to a value of 9 by addition of ammonia solution. The effect of LIX 664N concentration on extraction of nickel was studied. Up to 80% nickel could be extracted with 30% LIX 664N at O:A phase ratio of 2:1. Stripping of copper from the organic phase with 180 g/l sulfuric acid at O:A phase ratio of 1:1 gave 98.5% copper recovery in a two-stage operation.

关键词： Copper Nickel LIX 664N Solvent Extraction Distribution Coefficient Selectivity

Emerging role of roots in plant responses to aboveground insect herbivory

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Insect Science 2013年第3期20卷 286-296页

作者： Vamsi j. Nalam j.oti shah Punya Nachappa Department of Biology Indiana University-Purdue University Fort Wayne Indiana Department of Biological Sciences and Center for Plant Lipid Research University of North Texas Denton Texas United States

Plants have evolved complex biochemical mechanisms to counter threats from insect herbivory. Recent research has revealed an important role of roots in plant responses to above ground herbivory （AGH）. The involvement of roots is integral to plant resistance and tolerance mechanisms. Roots not only play an active role in plant defenses by acting as sites for biosynthesis of various toxins and but also contribute to tolerance by storing photoassimilates to enable future regrowth. The interaction of roots with beneficial soil- borne microorganisms also influences the outcome of the interaction between plant and insect herbivores. Shoot-to-root communication signals are critical for plant response to AGH. A better understanding of the role of roots in plant response to AGH is essential in order to develop a comprehensive picture of plant-insect interactions. Here, we summarize the current status of research on the role of roots in plant response to AGH and also discuss possible signals involved in shoot-to-root communication.

关键词： j.smonic acid secondary metabolites shoot-to-root communication soilborne microorganisms

The nature of the companion of PSR j.719-1438: a white dwarf or an exotic obj.ct?

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Research in Astronomy and Astrophysics 2012年第7期12卷 813-816页

作者： j. E. Horvath Instituto de Astronomia Geofísica e Ciências Atmosfricas - Universidade de So Paulo

We raise the possibility that the very dense, compact companion of PSR j.719-1438, which has a j.piter-like mass, is an exotic quark obj.ct rather than a light helium or carbon white dwarf. The exotic hypothesis naturally explains some of the observed features, and provides quite strong predictions for this system, to be confirmed or refuted in feasible future studies.

关键词： binary pulsars -- exotic matter-- pulsars: individual (PSR j.719-1438)

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Antimicrobial Profile of Lactic Acid Bacteria Isolated from Vegetables and Indigenous Fermented Foods of India against Clinical Pathogens Using Microdilution Method

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Biomedical and Environmental Sciences 2013年第9期26卷 759-764页

作者： Ami PATEL Nihir shah Padma AMBALAM j. B. PRAj.PATI Olle HOLST Asa Lj.NGH Department of Dairy Microbiology SMC College of Dairy Science Anand Agricultural University Department of Biotechnology Lund University Department of Medical Microbiology Lund University

In dairy and food industries lactic acid bacteria （LAB） have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing evidence that lactobacilli which inhabit the gastrointestinal tract develop antimicrobial activities and participate in the host＇s defence system[1]. During fermentation, most of the LAB produces a number of different compounds like organic acids, hydrogen peroxide, diacetyl, acetaldehyde, carbon dioxide, polysaccharides, and proteinaceous compounds called bacteriocins or bacteriocinogenic peptides.

关键词： Antimicrobial Profile of Lactic Acid Bacteria Isolated from Vegetables and Indigenous Fermented Foods of India against Clinical Pathogens Using Microdilution Method CFS

Fractional delay compensated discrete-time SMC for networked control system

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Digital Communications and Networks 2017年第2期3卷 112-117页

作者： D.H. shah A.j. Mehta Guj.rat Technological University Gujarat India Institute of Infrastructure Technology Research and Management Gujarat India

Time-varying network induced delay in the communication channel severely affects the performance of closed loop network control systems. In this paper, a novel idea of compensating the fractional time varying communication delay in the sliding Surface is presented. The fractional time delay in the sensor to controller and controller to actuator channel is approximated using the Thiran approximation technique to design the sliding surface. A discrete-time sliding mode control law is derived using the proposed surface that compensates fractional time delay in sensor to controller and controller to actuator channels for uncertain network control systems. The sufficient condition for closed loop stability of the system is derived using the Lyapunov function. The efficacy of the proposed strategy is supported by the simulation results.

关键词： Discrete-time sliding mode control Networked control Network delay

Comparative assessment of mechanical and chemical fluid diversion techniques during hydraulic fracturing in horizontal wells

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Petroleum Science 2023年第6期20卷 3582-3597页

作者： Maunish S.shah Subhash N.shah Drilling Cementingand Stimulation Research CenterDepartment of Petroleum EngineeringSchool of Energy TechnologyPandit Deendayal Energy UniversityRaisanGandhinagarGujaratIndia Mewbourne School of Petroleum and Geological Engineering The University of OklahomaNormanOKUSA

The application of fluid diversion during hydraulic fracturing is an evolving technology and has become popular amongst E&P operators over the past few *** primary obj.ctive of the fluid diversion is to improve hydraulic fracturing treatment by increasing stimulated reservoir volume and improving hydrocarbon *** is possible by achieving any of the following obj.ctives:creating uniform distribution of treatment slurry within the target zone;treating unstimulated and under-stimulated zones;or by increasing fracture density by creating a complex fracture *** fluid diversion application is also helpful in decreasing the number of stages(by increasing stage length)for multi-stage plug-n-perf(PnP)fracturing *** is also applied to prevent fracture-driven interactions between adj.cent wells,which is currently a maj.r issue,especially in *** addition,for successful refracturing treatment,the diverter application is essential for isolating the existing fractures and redirecting the treatment slurry to the desired unstimulated *** diversion methods can be broadly categorized into the mechanical and chemical *** established mechanical diversion techniques are frac plugs,expandable casing patches,expandable liners,swellable packers,straddle packer assembly,sand plugs,frac sleeves,perforation ball sealers,and limited entry *** different chemical diversion techniques are particulates,fibers,gels,surfactants,perforation pods,and composite *** paper describes the current status of established mechanical and chemical diverter technologies and examines their comparative advantages and *** techniques are suitable for diverter application,but the technique is selected based on the desired obj.ctive and conditions of the wellbore and *** general guidelines for selecting diversion techniques and operational considerations are also provided in the *** diagnosis of diversion treatme

关键词： Fluid diversion Diverter Diverting agents Multi-stage fracturing Hydraulic fracturing Horizontal well

A selective approach to the surgical management of periampullary cancer patients and its outcome

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Hepatobiliary & Pancreatic Diseases International 2014年第6期13卷 628-633页

作者： Omar j.shah Irfan Robbani Parveen shah Sadaf A Bangri Irfan j.Khan Mohammad Y Bhat Manmohan Singh Departments of Surgical Gastroenterology Sher-i-Kashmir Institute of Medical Sciences Srinagar Kashmir India Radiodiagnosis & Imaging Sher-i-Kashmir Institute of Medical Sciences Srinagar Kashmir India Pathology Sher-i-Kashmir Institute of Medical Sciences Srinagar Kashmir India Departments of Surgical Gastroenterology Sher-i-Kashmir Institute of Medical Sciences Srinagar Kashmir India Departments of Surgical Gastroenterology Sher-i-Kashmir Institute of Medical Sciences Srinagar Kashmir India

BACKGROUND： Pancreaticoduodenectomy is a high risk, complex, technically challenging operation associated with significant perioperative morbidity and mortality. This study on the surgical management of periampullary cancer patients is based on our experience in a period of nearly 13 years. METHODS： The study was conducted on two groups of patients： group A included 42 patients who were treated between j.nuary 2000 and September 2005 and group B included 134 patients who were treated between October 2005 to October 2012. Preoperative, intraoperative and postoperative details of all these patients were collected, tabulated and analyzed to assess the impact of the selective approach introduced in the department with effect from October 2005. RESULTS： Intraoperative details revealed highly significant differences in the management of the two groups of patients in respect of operative time （250.4 vs 126.6 minutes; P〈0.001）, operative blood loss （1070.2 vs 414.9 mL; P〈0.001） and intraoperative blood transfusion （1A vs 0.2 units; P〈0.001）. Variations between the two groups in the frequency of complications were found to be statistically insignificant. However, the difference between the two groups in the overall morbidity of patients （47.6% vs 26.1%; P=0.009） and the length of their hospital stay （11.8 vs 7.8 days; P〈0.001） were significant. CONCLUSION： A selective approach applied to the surgical management of periampullary cancer patients is a step in the right direction.

关键词： pancreaticoduodenectomy superior approach technique Whipple's operation