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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： jia-Shu Ma Zhi-Ning Huang jia-hao li Bang-Ping jiang Yan-Da liao Shi-Chen Ji Xing-Can Shen State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and Engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan jian-Ming Zhou Kang-Ning li Xiao-Fei Wang jian-Cheng liu Zhao-Hua Peng Zhuo liang Ai-ling li jian Zheng Qi-Wen Fan Yun-Ju li You-Bao Wang Zhi-Hong li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang jia-Ying-hao li Jun-Wen Tian jiang-lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-hao Zhu Yu-Wen Chen Yu-Chen jiang Tao Tian Jin-Long Ma Yi-Hui liu Jing-Yu Dong Run-Long liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping liu Bing Guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

两株降解细菌对高粱烟嘧磺隆药害的缓解与污染土壤的修复

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土壤通报 2024年第3期55卷 801-809页

作者：高海燕王馨婷郝佳丽张建华山西农业大学高粱研究所山西晋中030600 山西农业大学植物保护学院山西晋中030600

【目的】旨在获得除草剂烟嘧磺隆的高效降解菌株,并确定其对烟嘧磺隆污染土壤的降解效果和对高粱药害的缓解作用。【方法】从长期施用烟嘧磺隆污染土壤中富集分离筛选烟嘧磺隆高效降解菌,并运用盆栽和田间试验监测其接种效果。【结果】... 详细信息

【目的】旨在获得除草剂烟嘧磺隆的高效降解菌株,并确定其对烟嘧磺隆污染土壤的降解效果和对高粱药害的缓解作用。【方法】从长期施用烟嘧磺隆污染土壤中富集分离筛选烟嘧磺隆高效降解菌,并运用盆栽和田间试验监测其接种效果。【结果】分离获得XZ4和XZ62株菌,初步鉴定为弯曲假单胞菌(Pseudomonas geniculata)和假黄单胞菌(Pseudoxanthomonas sp.)。盆栽结果显示,当土壤中烟嘧磺隆浓度为0.05 mg kg^(-1)时,接种菌剂XZ4(108 CFU mL-1)和菌剂XZ6(109 CFU mL-1)处理42 d,对烟嘧磺隆的降解率分别为88.15%和83.78%,且可显著降低其对高粱株高、根长和鲜重的抑制程度。2株菌均可显著增加土壤细菌数量、降低土壤真菌数量,且接种量越大效果越明显;均可提高土壤蔗糖酶、脲酶和碱性磷酸酶活性,改善土壤微生态环境,分别在108和109 CFU mL-1浓度下对酶活性的影响最大。与菌株XZ6相比,菌株XZ4对各项指标的作用效果更好。田间试验显示,菌剂XZ4(450 kg hm^(-2))可以有效缓解30和60 g a.i hm^(-2)烟嘧磺隆对高粱药害的情况,提高高粱出苗率、叶绿素含量、株高和产量,降低病株率,高粱生长基本可恢复至空白处理(BK)水平。【结论】弯曲假单胞菌XZ4对烟嘧磺隆污染土壤有较好的修复能力,且可减轻烟嘧磺隆对高粱的药害程度。

关键词：弯曲假单胞菌假黄单胞菌烟嘧磺隆修复作用

不孕不育人群生育生活质量评价及其影响因素分析

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国际生殖健康／计划生育杂志 2024年第2期43卷 159-165页

作者：郝佳丽何玉洁(审校) 山西医科大学太原030001 山西医科大学第一医院生殖医学中心

生育生活质量量表(Fertility Quality of life Questionnaire,FertiQoL)是不孕不育人群生活质量测量的特异性量表。生育生活质量下降会影响不孕不育人群的治疗积极性及治疗依从性,从而影响患者的助孕结局。大量研究表明,不孕不育人群生... 详细信息

生育生活质量量表(Fertility Quality of life Questionnaire,FertiQoL)是不孕不育人群生活质量测量的特异性量表。生育生活质量下降会影响不孕不育人群的治疗积极性及治疗依从性,从而影响患者的助孕结局。大量研究表明,不孕不育人群生育生活质量各模块及维度均有受损,但影响因素及对不同维度的影响程度尚无统一结论。中国和国外不孕不育人群生育生活质量受损情况不同,中国患者治疗模块受损更严重,国外患者核心模块受损更严重。社会支持、心理韧性是生育生活质量的保护因素,焦虑、抑郁、述情障碍、生育压力、病耻感则与生育生活质量呈负相关。除此之外,性别、年龄、居住地、受教育程度及不孕年限等一般特征也是不孕不育人群生育生活质量的重要影响因素。但目前对于提高患者生育生活质量的干预措施及干预后临床妊娠率是否得到提升的研究尚不充分。

关键词：不育生活质量影响因素分析生殖技术,辅助体外受精胚胎移植授精,人工

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西方蜜蜂对氟吡呋喃酮和吡虫啉胁迫的响应

环境昆虫学报 2024年第4期46卷 856-865页

作者：陈金郝珈历高晶刘永军王强张丽代平礼吴艳艳中国农业科学院蜜蜂研究所资源昆虫高效养殖与利用全国重点实验室北京100093

因新烟碱类农药对蜜蜂高毒,作为其潜在替代品的氟吡呋喃酮(Flupyradifurone,FPF)受到广泛关注。由于FPF被认为对“蜜蜂安全”,可在作物开花期使用,因而蜜蜂可能存在长期接触FPF的现象。农药胁迫下蜜蜂机体生理指标的响应是解析农药慢性... 详细信息

因新烟碱类农药对蜜蜂高毒,作为其潜在替代品的氟吡呋喃酮(Flupyradifurone,FPF)受到广泛关注。由于FPF被认为对“蜜蜂安全”,可在作物开花期使用,因而蜜蜂可能存在长期接触FPF的现象。农药胁迫下蜜蜂机体生理指标的响应是解析农药慢性毒性的基础。本文比较了FPF和吡虫啉(Imidacloprid,IMI)对蜜蜂存活率、解毒和氧化应激相关酶类以及免疫和凋亡相关基因表达的影响,结果表明,两种农药对哺育蜂的慢性经口毒性相近,均显著降低存活率,导致中肠组织损伤和细胞死亡,并且引起氧化应激、解毒和免疫反应。此外,幸存蜜蜂可能通过抑制过氧化物酶活性和下调细胞凋亡基因表达耐受农药胁迫。以上结果为解析两种农药慢性毒性和抗农药蜂种选育提供一定的理论依据。

关键词：氟吡呋喃酮西方蜜蜂细胞凋亡氧化应激免疫和解毒

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： jia-hao Wang Rui Qiu An-Kang Hu Ye-Qi liu Zhen Wu Hui Zhang Jun-li li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Evolution and control of inclusions of Ti-bearing ultra-low carbon steel during the steelmaking process

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Metabolomic-based analysis reveals bile acid-mediated ovarian failure induced by low temperature in zebrafish

Progress in Natural Science:Materials International 2024年第3期34卷 585-590页

作者： Wenjun Ma Bin Chen Haibo li lixia hao jianguan Chen Yi jia Daozheng liu Shougang Research Institute of Technology Room 1107No.69Yangzhuang RoadShijingshan DistrictBeijing100043China Beijing Shougang co. ltdRoom 606Yang DianZi Town Riverside VillageQian'an064404China

This article investigates the evolution and control of inclusions in the smelting process of titanium containing ultra-low carbon *** industrial experiments,the influence of oxygen content before aluminum addition on inclusions in ultra-low carbon IF steel was explored,and the evolution process of inclusions was *** microstructure of different types of inclusions was observed using three-dimensional analysis *** has found that the oxygen content before aluminum addition has no significant effect on the final oxygen ***,under low aluminum and low oxygen conditions,the size of inclusions formed is small and difficult to float and *** if the cycle time is extended,the AF index of inclusions remains at a high *** three-dimensional morphology analysis of inclusions,it was found that alumina formed under high aluminum and high oxygen conditions is very dense,while inclusions are relatively loose under low aluminum and low oxygen *** addition,through the analysis of aluminum oxygen supersaturation before the formation of aluminum oxide inclusions,it was found that due to the low oxygen content,the nucleation rate of aluminum oxide in the early stage of inclusion formation is relatively low,and the inclusions grow along the trajectory of oxygen,ultimately forming polycrystalline aluminum oxide *** article also observed for the first time the initial three-dimensional morphology of Al Ti inclusions,providing a theoretical basis for further optimizing smelting processes and controlling inclusions.

关键词： Inclusions Ultra-low carbon steel Steelmaking process Morphology of Al_(2)O_(3) TiO_(x)complex oxide Al_(2)O_(3)cluster

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Zoological Research 2024年第4期45卷 791-804页

作者： Wen-hao li Zhi-Qiang li Meng-Di Bu jia-Zhen li liang-Biao Chen Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources Ministry of EducationCollege of Fisheries and Life SciencesShanghai Ocean UniversityShanghai 201306China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266237China International Research Center for Marine Biosciences Ministry of Science and TechnologyCollege of Fisheries and Life SciencesShanghai Ocean UniversityShanghai 201306China

As ectotherms, fish are highly sensitive to temperature fluctuations, which can profoundly impact their reproductive cycles. In this study, we investigated the fertility and histological characteristics of zebrafish(Danio rerio) ovaries exposed to a temperature gradient ranging from the thermopreferendum temperature of the species,27℃, to lower temperatures of 22℃, 20℃, and 13℃ over a period of two weeks. Comparative metabolomic(six biological replicates for each temperature) and transcriptomic(four biological replicates for each temperature) analyses were conducted under the four temperature conditions. Results indicated that lower temperatures inhibited oocyte development and differential metabolites were involved in steroid hormone production,antioxidant function, and lipid and protein *** reproductive hormones, increased proteolysis,and lipid degradation significantly impeded oocyte development and egg maturation. Notably, a significant increase in bile acid content was noted in the ovaries of the cold-treated fish, indicating that bile acids play a critical role in ovarian failure. Overall, these findings provide valuable insights into the mechanisms governing the reproductive response of fish to cold stress.

关键词： old stress Ovarian failure Metabolome Zebrafish

High-sensitive state perception method for inverter-fed machine turn insulation based on FrFT-Mel

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Global Energy Interconnection 2024年第2期7卷 155-165页

作者： Ruitian Fan Xing Lei Tao jia Menglong Qin hao li Dawei Xiang College of Electrical Power Engineering Shanghai University of Electric PowerShanghai 200090P.R.China State Grid Shanghai Municipal Electric Power Company Shanghai 200437P.R.China State Grid Technology College Shandong 250002P.R.China College of Electronics and Information Engineering Tongji UniversityShanghai 201804P.R.China

Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy *** winding turn insulation failure is the root cause of inverter-fed machine *** online monitoring of turn insulation health can detect potential safety risks promptly,but faces the challenge of weak characteristics of turn insulation *** study proposes an innovative method to evaluate the turn insulation state of inverter-fed machines by utilizing the fractional Fourier transform with a Mel filter(FrFT-Mel).First,the sensitivity of the high-frequency(HF)switching oscillation current to variations in turn insulation was analyzed within the fractional ***,an improved Mel filter is introduced,and its structure and parameters are specifically designed based on the features intrinsic to the common-mode impedance resonance point of the electrical ***,an evaluation index was proposed for the turn insulation state of inverter-fed *** results on a 3kW permanent magnet synchronous machine(PMSM)demonstrate that the proposed FrFT-Mel method significantly enhances the sensitivity of turn insulation state perception by approximately five times,compared to the traditional Fourier transform method.

关键词： State perception Turn insulation Switching oscillation Fractional Fourier transform Mel filter

Deep eutectic solvent-driven self-assembly of metal mercaptide complexes with enzyme-mimicking activities for detection of uric acid through one-step cascade catalytic reaction

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Green Chemical Engineering 2024年第1期5卷 75-84页

作者： Jean Claude Munyemana jia Chen Xin li Yangxia Han hao Tang Hongdeng Qiu CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100039China Department of Pharmacy Gansu Provincial HospitalLanzhou730000China

This work presents a generic strategy to create a series of metal mercaptides complexes via coordination selfassembly between transition metals(Mn,Cu,Co,Fe,and Ni)and cysteine(Cys)by forming the sulfur-metal *** strategy involves dissolving metal chlorides and Cys into deep eutectic solvents(DES),followed by the precipitation of metal mercaptides complexes(such as Cys-Mn)by adding water as an antisolvent,where DES serves as the solvent,shape directing,and capping agent,thereby preventing the formation of other metal ***,the prepared complexes possess both laccase and peroxidase-like properties,allowing the design of a technique for the detection of L-3,4-dihydroxyphenylalanine(L-DOPA)and uric acid,*** prepared Cys-Mn can linearly oxidize L-DOPA with its concentrations from 0.1 to 130μM and the detection limit was calculated to be 75.5 n ***,the Cys-Mn can mimic the activity of peroxidase towards oxidization of o-phenylenediamine at neutral p H,allowing single-step and one-pot cascade reactions for visual and fluorometric measurements of uric acid(UA)that could work in the range of 0.2-500μM UA with a detection limit of 0.06μM and 0.054μМ,*** assay was successful in detecting UA in serum and urine samples with relative standard deviation(RSD)ranging from 7.3%to 10.2%and 3.0%-8.5%respectively,suggesting that it may prove useful in medical diagnostic testing.

关键词： Metal-mercaptides Deep eutectic solvents Self-assembly Peroxidase-mimic catalyst Uric acid detection