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Chinese journal of Polymer Science 2014年第12期32卷 1690-1703页

作者： j.h.trivedi M.D.Thaker h.C.trivedi P.G. Department of Chemistry Sardar Patel University

Photo-induced graft copolymerization of methyl methacrylate（MMA） onto sodium salt of partially carboxymethylated guar gum（Na-PCMGG, DS = 0.291） was carried out in an aqueous medium using ceric ammonium nitrate（CAN） as photoinitiator to synthesize a novel graft copolymer, Na-PCMGG-g-PMMA, which may find its potential application as a metal adsorbent. The influences of synthesis variables such as concentrations of photoinitiator（CAN）, nitric acid and monomer（MMA） as well as reaction time, temperature and amount of substrate on the grafting yields were studied and the reaction conditions for optimum photo-grafting were evaluated. At optimum concentration, the maximum values of the grafting yields achieved were G = 271.61% and GE = 63.89%. The experimental results were found to be in very good agreement with the proposed kinetic scheme. The photo-graft copolymerization of MMA onto Na-PCMGG（ DS = 0.291） was also carried out in the presence and absence of ultraviolet radiation for studying the efficiency of the photoinitiator. The influence of carboxymethyl groups introduced onto the guar gum molecules with regard to its behavior towards ultra-violet radiation induced grafting with MMA was also investigated. Photo-grafting process was confirmed and the products were characterized with the help of the spectroscopic（1h-NMR and FTIR） and SEM techniques.

关键词： Photo-induced grafting Methyl methacrylate Sodium salt of partially carboxymethylated guar gum Optimum reaction conditions Characterization.

MODIFICATION OF SODIUM SALT OF PARTIALLY CARBOXYMEThYLATED TAMARIND KERNEL POWDER ThROUGh GRAFTING WITh ACRYLONITRILE: SYNThESIS, ChARACTERIZATION AND SWELLING BEhAVIOR

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Chinese journal of Polymer Science 2013年第12期31卷 1670-1684页

作者： j.h.trivedi j.R.jivani K.h.Patel h.C.trivedi P.G.Dept.of Chemistry Sardar Patel UniversityVallabh Vidyanagar Amneal Phamaceuticals

A graft copolymer of polyacrylonitrile （PAN） with sodium salt of partially carboxymethylated tamarind kernel powder （Na-PCMTKP, DS ^-= 0.15） was synthesized by using ceric ammonium nitrate （CAN） as a redox initiator in an aqueous medium. The optimum reaction conditions for affording maximum percentage of grafting were established by successively varying reaction conditions such as concentrations of nitric acid, CAN, monomer （AN） as well as reaction time, temperature and amount of substrate. The influence of these reaction conditions on the grafting yields was discussed. The kinetic scheme of free radical graft copolymerization was proposed and the experimental results were found to agree very well with the proposed kinetic scheme. The graft copolymer （Na-PCMTKP-g-PAN, percentage of grafting G = 413.76% and percentage of grafting efficiency GE = 96.48%） sample synthesized under the established optimized reaction conditions was hydrolyzed by 0.7 mol-L l NaOh solution at 90-95 ℃ to yield the superabsorbent hydrogel, h-Na-PCMTKP-g-PAN. The swelling behavior of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15 mol·L^-1 salt （NaCl, CaCl2 and AlCl3） solutions and simulated urine （SU） solution at different timings. FTIR, TGA and SEM techniques were used to characterize the products.

关键词： Sodium salt of partially carboxymethylated tamarind kernel powder Acrylonitrile Graft copolymerization Superabsorbent hydrogels Swelling behavior.

Organophosphate pesticides an emerging environmental contaminant: Pollution, toxicity, bioremediation progress, and remaining challenges

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journal of Environmental Sciences 2023年第5期127卷 234-250页

作者： himanshu Mali Chandni Shah B.h.Raghunandan Anil S.Prajapati Darshan h.Patel Ujjval trivedi R.B.Subramanian P.G.Department of Biosciences UGC-Centre of Advanced StudiesSatellite CampusSardar Patel UniversitySardar Patel MaidanBakrol-Vadtal RoadBakrol 388315GujaratIndia Charotar Institute of Paramedical Sciences Charotar University of Science and Technology(CHARUSAT)Changa 388421GujaratIndia

Organophosphates(OPs)are an integral part of modern agriculture;however,due to overexploitation,OPs pesticides residues are leaching and accumulating in the soil,and groundwater contaminated terrestrial and aquatic food *** exposure to OPs could produce toxicity in insects,plants,animals,and *** are known for covalent inhibition of acetylcholinesterase enzyme in pests and terrestrial/aquatic organisms,leading to nervous,respiratory,reproductive,and hepatic *** pesticides also disrupt the growth-promoting machinery in plants by inhibiting key enzymes,permeability,and trans-cuticular diffusion,which is crucial for plant *** use of OPs,directly/indirectly affecting human/environmental health,raise a thoughtful global *** a safe,reliable,economical,and eco-friendly methods for removing OPs pesticides from the environment is thus *** techniques coupled with microbes or microbial-biocatalysts are emerging as promising antidotes for OPs ***,we comprehensively review the current scenario of OPs pollution,their toxicity(at a molecular level),and the recent advancements in biotechnology(modified biocatalytic systems)for detection,decontamination,and bioremediation of OP-pesticides in polluted ***,the review focuses on onsite applications of OPs degrading enzymes(immobilizations/biosensors/others),and it also highlights remaining challenges with future approaches.

关键词： Organophosphorus compounds Toxicity Bioremediation Microorganisms Enzymes Biosensors

Clinical,laboratory,and therapeutic differences between immunoglobulin E-mediated and non-immunoglobulin E-mediated cow’s milk protein allergy in children

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World journal of Clinical Pediatrics 2025年第1期14卷 78-92页

作者： hasan M Isa Marwa j Abdulnabi Nawra S Naser Fatema N Lahmda Noor M AlAnsari Zahra h Isa Afaf M Mohamed Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Faculty of Medicine Mansoura UniversityMansoura 35516Egypt Public health Directorate Ministry of HealthManama 26671Bahrain

BACKGROUND Although breast milk is ideal for newborns,in some cases,it is replaced with cow’s milk,which contains proteins that increase the risk of cow’s milk protein allergy(CMPA).AIM To evaluate CMPA prevalence in Bahrain and compare clinical characteristics of children with immunoglobulin E(IgE)-and non-IgE-mediated *** This retrospective cohort study examined children with CMPA diagnosed at the pediatric gastroenterology outpatient clinic of the Salmaniya Medical Complex,Bahrain,between 2014 and 2022,and assessed CMPA *** presentations,laboratory findings,dietary modifications,and outcomes were compared between children with IgE-mediated and non-IgE-mediated *** variables were compared using Fisher’s exact test or Pearson’sχ2 test,whereas continuous variables were compared using Student’s t-test or the Mann-Whitney U *** Of 8332 patients,6022(72.3%)adhered to their *** them,618(10.3%)were suggested of having CMPA and 595(96.3%)were included;CMPA prevalence was 2%.Most patients were Bahraini(93.8%)and males(55.3%).Non-IgE-mediated type accounted for 77.3%cases and IgE-mediated type,22.7%.IgE-mediated CMPA presented more in boys(P=0.030),and later in life(5.1 months±4.5 months vs 4.2 months±4.2 months,P=0.016,95%CI:0.08-1.73),had more associated diseases(Ph more cutaneous(P=0.024)and respiratory(P=0.003)manifestations,severe symptoms[rash/dry skin(P=0.031),facial swelling/angioedema(P=0.003),failure to thrive(P=0.013),apparent life-threatening event(Physical findings(P=0.002)than non-IgE-mediated *** patients were exclusively fed cow milk formula(50.3%).The amino acid-based formula(AAF)was most prescribed(60.5%)with no difference between the two types(P=0.173).Although breastfeeding was recommended to 49.6%,only 8.2%were exclusively ***-mediated CMPA was associated with a longer follow-up duration than non-IgE-mediated CMPA(17.3 months±14.0 mo

关键词： Children Milk allergy Immunoglobulin E Breastfeeding Infant formula Bahrain

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn j.W.So Konstantin Feinberg Marina Manoraj jenny Cheung jennifer Zhang Kaveh Mirmoeini jPaul Santerre Tessa Gordon Gregory hBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Plasma density measurement and downstream etching of silicon and silicon oxide in Ar/NF3 mixture remote plasma source

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Plasma Science and Technology 2019年第6期21卷 52-57页

作者： h j YEOM D h ChOI Y S LEE j h KIM D j SEONG S j YOU h C LEE Korea Research Institute of Standards and Science(KRISS) Daejeon 34113 Republic of Korea Department of Physics Chungnam National University Daejeon 34134 Republic of Korea

In this study,plasma density measurements were performed near the plume region of the remote plasma source (RPS) in Ar/NF3 gas mixtures using a microwave cutoff *** measured plasma density is in the range of 1010-1011 cm-3 in the discharge conditions with RPS powers of 2-4 kW and gas pressures of 0.87-4 *** plasma density decreased with increasing gas pressures and RPS powers under various Ar/NF3 mixing *** decrease in the plasma density measured at the fixed measurement position (plume region) can be understood by the reduction of the electron energy relaxation length with increases in the gas pressures and mixing ratio of NF3/(Ar/NF3).We also performed downstream etching of silicon and silicon oxide films in this *** etch rate of the silicon films significantly increases while the silicon oxide is slightly etched with the gas pressures and *** was also found that the etch rate strongly depends on the wafer position on the processing chamber electrode,and that the etch selectivity reached 96-131 in the discharge conditions of RF powers (3730-4180 W) and gas pressures (3.6-4 Torr).

关键词： remote plasma source electron density cutoff probe downstream etch

A structural topological optimization method for multi-displacement constraints and any initial topology configuration

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Acta Mechanica Sinica 2010年第5期26卷 735-744页

作者： j. h. Rong j. h. Yi School of Automotive and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-based topological design, one expects that the final result consists of elements either black （solid material） or white （void）, without any grey areas. Moreover, one also expects that the optimal topology can be obtained by starting from any initial topology configuration. An improved structural topological optimization method for multidisplacement constraints is proposed in this paper. In the proposed method, the whole optimization process is divided into two optimization adjustment phases and a phase transferring step. Firstly, an optimization model is built to deal with the varied displacement limits, design space adjustments, and reasonable relations between the element stiffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve the optimization problem formulated in the first optimization adjustment phase, by starting with a small design space and advancing to a larger deign space. The design space adjustments are automatic when the design domain needs expansions, in which the convergence of the proposed method will not be affected. The final topology obtained by the proposed procedure in the first optimization phase, can approach to the vicinity of the optimum topology. Then, a heuristic algorithm is given to improve the efficiency and make the designed structural topology black/white in both the phase transferring step and the second optimization adjustment phase. And the optimum topology can finally be obtained by the second phase optimization adjustments. Two examples are presented to show that the topologies obtained by the proposed method are of very good 0/1 design distribution property, and the computational efficiency is enhanced by reducing the element number of the design structural finite model during two optimization adjustment phases. And the examples also show that this method is robust and practicable.

关键词： Topological optimization Displacement constraint Continuum structure Design space adjustment Rational approximation material model

Large signal of h → μτ within the constraints of e_(i) → e_(j)γ decays in the 3-3-1 model with neutral leptons

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Chinese Physics C 2022年第12期46卷 106-125页

作者： h.T.hung D.T.Binh h.V.Quyet Department of Physics Hanoi Pedagogical University 2Phuc YenVinh Phuc 15000Vietnam Institute of Theoretical and Applied Research Duy Tan UniversityHanoi 10000Vietnam Faculty of Natural Science Duy Tan UniversityDa Nang 50000Vietnam

In the framework of the 3-3-1 model with neutral leptons,we investigate lepton-flavor-violating sources based on the higgs mass spectrum,which has two neutral higgs identified with the corresponding ones of the two-higgs-doublet *** note that at the 13TeV scale of the LhC,the parameter space regions satisfy the experimental limits of e_(i)→e_(j)γ*** regions depend heavily on the mixing of exotic leptons but are predicted to have large h_(1)^(0)→μτ*** also show that Br(h_(1)^(0)→μτ)can reach a value of 10^(-4).

关键词： higgs boson electroweak interaction beyond the SM LFV decays

Optimal use of mobile cooling units in a deep-level gold mine

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International journal of Mining Science and Technology 2020年第4期30卷 547-553页

作者： h.j.van Staden j.F.van Rensburg h.j.Groenewald Centre for Research and Continued Engineering Development North-West UniversityPretoria 0081South Africa

The South African gold mining sector remains a significant contributor to the country’s *** several challenges that hinder the realisation of South Africa’s full mineral potential,the sector’s sustainability and profitability can be enhanced through implementing operational improvement *** cooling units(MCUs)were identified as a potential focus area for operational *** are used as tertiary or in-stope cooling in hot underground *** this paper,a method was presented to characterise the performance of existing MCUs based on three key performance indicators(KPIs),namely,the wet-bulb temperature ratio(WTR),efficiency and *** strategies were then elected and implemented based on these *** implementation of this method in a South African gold mine attained a reduction in pumped water volumes,reduced operating costs through electricity cost savings and improvements in underground ventilation air temperatures.

关键词： Mobile cooling units Optimisation Mine cooling performance Electricity cost savings Spot cooling

Experimental investigation on the enhanced oil recovery efficiency of polymeric surfactant: Matching relationship with core and emulsification ability

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Petroleum Science 2023年第1期20卷 619-635页

作者： Xin Chen Yi-Qiang Li Zhe-Yu Liu japan trivedi Wen-Bin Gao Ming-Yue Sui State Key Laboratory of Oil and Gas Resources and Exploration School of Petroleum EngineeringChina University of Petroleum(Beijing)Beijing 102249China Faculty of Engineering-Civil and Environmental Engineering University of AlbertaEdmontonAlberta T6G 2R3Canada Institute of Rock and Soil Mechanics Chinese Academic of SciencesWuhanHubei 430071China PetroChina Changqing Oilfield Co Research Institute of Oilfield Exploration and Development XianShaanxi 710018China

The polymeric surfactant can be used as an efficient agent for enhanced oil recovery(EOR)because of its large bulk viscosity and good interfacial ***,there is a sparse understanding of its matching relationship with reservoirs and emulsification occurrence conditions,which may affect its migration and EOR *** intermolecular association molecule polymeric surfactant(IAM)was synthesized by micellar polymerization and characterized with 1 h NMR,FTIR,and *** matching relationship between IAM and reservoirs was evaluated by comparing the viscosity retention rate of effluent in the core flow ***,the effect of the matching relationship on EOR in the heterogeneous reservoir was clarified with parallel core displacement experiments by considering different flow abilities of IAM in the high-permeability *** occurrence conditions of in-situ emulsification of IAM were evaluated via oil-water co-injection experiments under the different injection rates and oil-water *** visualization displacement was carried out to compare the micro EOR mechanisms of different chemical *** results show that IAM features thickening,shearing resistance,viscoelasticity,thermal stability,and interfacial *** matching relationship between cores and IAM could be divided as hardly injected,flow limited,and flow smoothly,corresponding to the viscosity retention ratio of80%,*** could gain better EOR efficiency(17.69%)when its matching relationship to the high permeability layer was“flow limited”.The defined mixture capillary number shows that only when it is greater than 1×10^(3),the in-situ emulsions can be *** to hPAM,IAM could reduce IFT and form vortices to more effectively displace film and corner remaining oils by stripping and peeling off crude *** formed emulsion accumulated at the pore throat could further increase flow resistance,which benefits swept area enlargemen

关键词： Migration Matching relationship Viscosity retention ratio Emulsion EOR