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^(14)C-氯氰菊酯农药在“微宇”环境中的迁移、归宿

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环境科学 1990年第5期11卷 2-6页

作者：周振惠 r.viswanathan 中国科学院上海昆虫研究所西德GSF.生态化学研究所

本文在“微宇”环境中研究^(14)C-氯氰菊酯在玉米-土壤-土壤动物相间的质量平衡、吸收、结合残留、迁移和转化规律。实验结果表明,植物通过根部从土壤中吸收少量氯氰菊酯,并通过叶脉输导,但向上输导能力差,无内吸作用。它在土壤中性质... 详细信息

本文在“微宇”环境中研究^(14)C-氯氰菊酯在玉米-土壤-土壤动物相间的质量平衡、吸收、结合残留、迁移和转化规律。实验结果表明,植物通过根部从土壤中吸收少量氯氰菊酯,并通过叶脉输导,但向上输导能力差,无内吸作用。它在土壤中性质较稳定,被动、植物吸收的药剂,在植物体内主要转化为结合态;在动物中则主要为代谢作用。它在土壤中以酯链断裂为主要降解路线,其次为4′-位置上羟化,再经土壤甲基化作用生成4′-甲氧基代谢物。

关键词：农药微宇环境迁移归宿结合残留

氯氰菊酯农药中杂质及立体异构体的分离、鉴定

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农药 1989年第6期28卷 11-12,10页

作者：周振惠 r.viswanathan 中国科学院上海昆虫研究所西德辐射与环境研究中心生态化学研究所

本文应用薄层色谱、气相色谱法分离了氯氰菊酯原药中的立体异构体和主要杂质。经GC-MS鉴定,其主要杂质为3-(2,2-二氯乙烯基)2,2-二甲基环丙烷羧酸,3-含氧基苯基安息香醛,3-含氧基苯基安息香醇及3-含氧基甲基偶联苯。它们与该农药在动物... 详细信息

本文应用薄层色谱、气相色谱法分离了氯氰菊酯原药中的立体异构体和主要杂质。经GC-MS鉴定,其主要杂质为3-(2,2-二氯乙烯基)2,2-二甲基环丙烷羧酸,3-含氧基苯基安息香醛,3-含氧基苯基安息香醇及3-含氧基甲基偶联苯。它们与该农药在动物和土壤中的主要代谢物相同。

关键词：立体异构体安息香醛薄层色谱甲基环氯氰菊酯薄层板气相色谱法反式异构体氯氰菊醋烯基

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发电机护环用材料

大型铸锻件 1983年第2期 83-93,73页

作者： r.viswanathan 张明芳

护环是发电机中承受应力最高的部件之一,它的完整性是发电机运行安全可靠的关键。流行的护环用钢对应力腐蚀开裂敏感,屈服强度极限在1200MPa左右。使用改善了机械性能的替代材料,就可以提高发电机的可靠性、有效性、尺寸容量和实用性。... 详细信息

护环是发电机中承受应力最高的部件之一,它的完整性是发电机运行安全可靠的关键。流行的护环用钢对应力腐蚀开裂敏感,屈服强度极限在1200MPa左右。使用改善了机械性能的替代材料,就可以提高发电机的可靠性、有效性、尺寸容量和实用性。本文是一篇有关护环材料的工艺发展水平的述评。

关键词：护环材料替代材料发电机应力腐蚀开裂安全可靠电机运行强度极限机械性能

2(1/4)Cr-1Mo钢在煤转化压力容器上的应用

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流体机械 1983年第8期 50-57+64页

作者： r.viswanathan r.I.Jaffee 倪寿刚

2（1/4）Cr—1Mo钢在用于煤气化和液化压力容器外壳时,由于受高压、高温和产品中H2、H2S、CO、CO2、NH3及其它多种有机和无机化合物的影响,压力容器壳体的完整性将会受到回火脆性、氢脆及氢腐蚀的作用而受到削弱。本文主要就电力研究所... 详细信息

2（1/4）Cr—1Mo钢在用于煤气化和液化压力容器外壳时,由于受高压、高温和产品中H2、H2S、CO、CO2、NH3及其它多种有机和无机化合物的影响,压力容器壳体的完整性将会受到回火脆性、氢脆及氢腐蚀的作用而受到削弱。本文主要就电力研究所关于2（1/4）Cr-1Mo钢回火脆性、氢脆等研究结果加以评述,以探讨其损伤机理对煤化压力容器设计的影响。

关键词：压力容器 Cr-1Mo 氢腐蚀回火脆化氢脆煤转化 Mo

A review on transition metal oxides based photocatalysts for degradation of synthetic organic pollutants

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Journal of Environmental Sciences 2024年第5期139卷 389-417页

作者： Athira Krishnan Anna Swarnalal Divine Das Midhina Krishnan viswanathan S.Saji SMAShibli Department of Chemistry Amrita Vishwa VidyapeethamAmritapuriKerala690525India Interdisciplinary research Center for Advanced Materials King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Chemistry University of KeralaKariavattom CampusThiruvananthapuramKerala695581India

This review provides insight into the current research trend in transition metal oxides(TMOs)-based photocatalysis in removing the organic colouring matters from *** easy understanding,the research progress has been presented in four generations according to the catalyst composition and mode of application,viz:single component TMOs(the firstgeneration),doped TMOs/binary TMOs/doped binary TMOs(the second-generation),inactive/active support-immobilized TMOs(the third-generation),and ternary/quaternary compositions(the fourth-generation).The first two generations represent suspended catalysts,the third generation is supported catalysts,and the fourth generation can be suspended or *** review provides an elaborated comparison between suspended and supported catalysts,their general/specific requirements,key factors controlling degradation,and the methodologies for performance *** the plausible fundamental and advanced dye degradation mechanisms involved in each generation of catalysts were *** existing challenges in TMOs-based photocatalysis and how the researchers approach the hitch to resolve it effectively are *** research trends are also presented.

关键词： Photocatalysis Dye degradation Transition metal oxides and composites Supported catalysts Suspended catalysts

Does progress in microfracture techniques necessarily translate into clinical effectiveness?

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World Journal of Orthopedics 2024年第3期15卷 266-284页

作者： Sathish Muthu Vibhu Krishnan viswanathan Manoharan Sakthivel Mohammed Thabrez Department of Orthopaedics Orthopaedic Research GroupCoimbatore 641045Tamil NaduIndia Department of Biotechnology Karpagam Academy of Higher EducationCoimbatore 641021Tamil NaduIndia Manoharan Sakthivel Department of OrthopaedicsGovernment Medical CollegeKarur 639004Tamil NaduIndia Department of Orthopaedics Devadoss Multispecialty HospitalMadurai 625007Tamil NaduIndia Department of Medical Oncology Aster Medcity HospitalKochi 682034India

BACKGrOUND Multitudinous advancements have been made to the traditional microfracture(MFx)technique,which have involved delivery of various acellular 2nd generation MFx and cellular MFx-III components to the area of cartilage *** relative benefits and pitfalls of these diverse modifications of MFx technique are still not widely *** To comparatively analyze the functional,radiological,and histological outcomes,and complications of various generations of MFx available for the treatment of cartilage *** A systematic review was performed using PubMed,EMBASE,Web of Science,Cochrane,and *** of any age and sex with cartilage defects undergoing any form of MFx were considered for *** included only randomized controlled trials(rCTs)reporting functional,radiological,histological outcomes or complications of various generations of MFx for the management of cartilage *** meta-analysis(NMA)was conducted in Stata and Cochrane’s Confidence in NMA approach was utilized for appraisal of *** Forty-four rCTs were included in the analysis with patients of mean age of 39.40(±9.46)*** comparing the results of the other generations with MFX-I as a constant comparator,we noted a trend towards better pain control and functional outcome(KOOS,IKDC,and Cincinnati scores)at the end of 1-,2-,and 5-year time points with MFx-III,although the differences were not statistically significant(P>0.05).We also noted statistically significant Magnetic resonance observation of cartilage repair tissue score in the higher generations of microfracture(weighted mean difference:17.44,95%confidence interval:0.72,34.16,P=0.025;without significant heterogeneity)at 1 ***,the difference was not maintained at 2 *** was a trend towards better defect filling on MrI with the second and third generation MFx,although the difference was not statistically significant(P>0.05).CONCLUSION The higher generations of traditional MFx

关键词： Cartilage injury Microfracture Mesenchymal stem cells Platelet-rich plasma Bone marrow aspiration concentrates Clinical outcome radiological outcome Meta-analysis Network meta-analysis

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

Characterization of tumors of jaw:Additive value of contrast enhancement and dual-energy computed tomography

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World Journal of radiology 2024年第4期16卷 82-93页

作者： Deepak Justine viswanathan Ashu Seith Bhalla Smita Manchanda Ajoy roychoudhury Deepika Mishra Asit ranjan Mridha Department of radiodiagnosis and Interventional radiology All India Institute of Medical SciencesNew Delhi 110029India Department of Oral and Maxillofacial Surgery All India Institute of Medical SciencesNew Delhi 110029India Department of Oral Pathology and Microbiology All India Institute of Medical SciencesNew Delhi 110029India Department of Pathology All India Institute of Medical SciencesAnsari NagarNew Delhi 110029India

BACKGrOUND Currently,the differentiation of jaw tumors is mainly based on the lesion’s morphology rather than the enhancement characteristics,which are important in the differentiation of neoplasms across the *** is a paucity of literature on the enhancement characteristics of jaw *** is mainly because,even though computed tomography(CT)is used to evaluate these lesions,they are often imaged without intravenous *** study hypothesised that the enhancement characteristics of the solid component of jaw tumors can aid in the differentiation of these lesions in addition to their morphology by dual-energy CT,therefore improving the ability to differentiate between various *** To evaluate the role of contrast enhancement and dual-energy quantitative parameters in CT in the differentiation of jaw *** Fifty-seven patients with jaw tumors underwent contrast-enhanced dual-energy *** analysis of the tumor,including the enhancing solid component,was done,followed by quantitative analysis of iodine concentration(IC),water concentration(WC),HU,and normalized *** study population was divided into four subgroups based on histopathological analysis-central giant cell granuloma(CGCG),ameloblastoma,odontogenic keratocyst(OKC),and other jaw tumors.A one-way ANOVA test for parametric variables and the Kruskal-Wallis test for nonparametric variables were *** significant differences were found,a series of independent t-tests or Mann-Whitney U tests were *** Ameloblastoma was the most common pathology(n=20),followed by CGCG(n=11)and *** showed a higher mean concentration of all quantitative parameters than ameloblastomas(Preshold of 31.35×100μg/cm^(3) had the maximum sensitivity(81.8%)and specificity(65%).Between ameloblastomas and OKC,the former showed a higher mean concentration of all quantitative parameters(Pr when comparing unilocular ameloblastomas with OKCs,the latter showed

关键词： Jaw neoplasms Ameloblastomas Dual-energy computed tomography Iodine quantification Mandibular neoplasms Maxillary neoplasms

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric r.Hoglund Andrew r.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations