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Journal of Materials Science and Chemical Engineering 2025年第1期13卷 20-44页

作者： hao Duan Xiaoyan Shang Xihao Wu Liuliu Ma Chen xing Jun Zhu Department of Materials Science Fudan University Shanghai China Fineblend Polymer (Shanghai) Co. Ltd. Shanghai China National Engineering Research Center for Nanotechnology Shanghai China

Amid the escalating plastic pollution issue, the development of biodegradable and recyclable polymeric materials has become a focus within the scientific community. Chain extenders, which are an important class of compounds, facilitate the elongation of polymer chains through reactive functional groups, thereby enhancing the performance of the materials. Epoxy-based chain extenders, due to their cost-effectiveness, low toxicity, high reaction efficiency, and effective reactivity with hydroxyl and carboxyl groups, have emerged as a promising class of chain extenders. This manuscript comprehensively elaborates on the varieties, structural characteristics, and performance of chain extenders, the challenges they face, and the methods for their modification. Special emphasis is placed on the application of epoxy-based chain extenders in biodegradable polymers, such as polylactic acid (PLA), and their subsequent influence on the structural and performance properties of these materials.

关键词： Chain Extender Epoxy Type GMA Biodegradable PLA Recycle

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角形自由流电泳装置的设计与应用研究

分析化学 2013年第6期41卷 856-860页

作者：张衡瑞李建波于好兴董靖宇曹成喜张维冰齐齐哈尔大学华东理工大学山东中矿集团有限公司上海交通大学

基于自由流电泳(Free flow electrophoresis,FFE)原理设计一种新型角形FFE装置,与传统矩形装置相比,新型装置分离腔设计为角形,运行时单管进样,样品由泵推动前移形成层流,避免缓冲液使用,显著降低了仪器运行成本。研究了角形装置构造和... 详细信息

基于自由流电泳(Free flow electrophoresis,FFE)原理设计一种新型角形FFE装置,与传统矩形装置相比,新型装置分离腔设计为角形,运行时单管进样,样品由泵推动前移形成层流,避免缓冲液使用,显著降低了仪器运行成本。研究了角形装置构造和电场分布理论,在优化的分离条件U=400 V、v=0.5 mL/min时,成功分离了中性红和亚甲基兰混合液。在传统矩形装置上U=70 V、v=1.0 mL/min条件下,山东某金矿贵液经分离,杂质铜与锌降低至51.46%与58.87%;相同条件下,在角型FFE装置上,铜与锌减少至52.77%和53.94%,即角形装置可以达到与传统矩形装置同等分离效果,并减少了背景缓冲液的使用。因此,此装置有望在大规模样品连续分离方面发挥重要作用。

关键词：自由流电泳场强分布矩形装置角形装置金矿贵液分离

缓释肥处理下麦田土壤细菌和真菌群落对气候变化的响应

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中国土壤与肥料 2022年第10期 50-63页

作者：任宏芳王璐郝兴宇张东升宗毓铮李萍山西农业大学农学院山西太谷030801

采用控制系统来模拟未来大气CO_(2)浓度和气温升高的气候变化情景,借助基于半导体芯片技术的IonS5^(TM)XL测序平台并结合相关生物信息学方法对气候变化背景下缓释肥处理的麦田土壤进行16S rRNA细菌V4区和18S rRNA真菌ITS区测序分析,探... 详细信息

采用控制系统来模拟未来大气CO_(2)浓度和气温升高的气候变化情景,借助基于半导体芯片技术的IonS5^(TM)XL测序平台并结合相关生物信息学方法对气候变化背景下缓释肥处理的麦田土壤进行16S rRNA细菌V4区和18S rRNA真菌ITS区测序分析,探究了缓释肥处理下麦田土壤细菌和真菌对气候变化的响应。结果显示,所有样品测序后获得细菌和真菌平均有效序列数分别是80543和64303个,平均OTUs分别是3149和1161个。Alpha多样性分析显示,大气CO_(2)浓度升高小麦土壤细菌的Shannon和Chao1指数均降低,而土壤真菌在各气候环境下均无显著差异。主成分分析显示,各处理下土壤细菌群落结构差异不明显,真菌群落结构在气温升高时差异明显。缓释肥处理与普通肥相比,土壤细菌和真菌的Alpha多样性及群落结构在不同气候条件下均没有差异。菌群分类学表明,小麦土壤的优势细菌门为变形菌门、放线菌门、拟杆菌门和酸杆菌门,主要的优势细菌属有9种;优势真菌门为子囊菌门、被孢菌门和担子菌门,主要的优势真菌属有7种。大气CO_(2)浓度升高条件下,施用普通尿素使变形菌门和鞘氨醇单胞菌属的相对丰度分别增加10.34%和46.27%。在对照温度对照CO_(2)浓度条件下,缓释肥处理比普通肥处理使子囊菌门和毛壳菌属相对丰度分别显著增加39.85%和295.33%;在升高温度对照CO_(2)浓度条件下,缓释肥处理比普通肥处理使子囊菌门和毛壳菌属分别增加33.16%和154.49%。CO_(2)对变形菌门、鞘氨醇单胞菌属和毛壳菌属的影响达显著水平。在各气候变化环境下,各土壤理化性质均有所改善;与普通氮肥相比,缓释氮肥处理在各气候环境下土壤有机质、碱解氮和全氮含量降低,土壤有效磷和总磷含量升高。冗余分析表明,土壤细菌群落结构主要受土壤全氮和盐分含量的影响,而真菌群落结构主要受土壤pH和有效磷含量的影响。研究结果表明,未来气候环境变化对土壤微生物群落的影响大于缓释肥处理。该结果加深了缓释肥对土壤微生物群落结构和多样性影响的认识,为未来气候环境变化下缓释肥推广使用提供理论依据。

关键词：气候变化大气CO_(2)浓度升高温度升高缓释肥土壤微生物高通量测序

大气CO_(2)浓度升高对干旱条件下冬小麦叶片光合适应的影响

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应用生态学报 2021年第12期32卷 4370-4380页

作者：宗毓铮杨琦常翠翠勾俊英张东升郝兴宇高志强山西农业大学农学院山西晋中030801

大气CO_(2)浓度升高是全球气候变化的主要特征,但大气CO_(2)浓度长期升高条件下冬小麦叶片发生光合适应的机制尚不十分清楚。本研究以盆栽冬小麦‘郑麦9023’为试验材料,在人工气候控制室内设置2个CO_(2)浓度(400和600μmol·mol^(-1))... 详细信息

大气CO_(2)浓度升高是全球气候变化的主要特征,但大气CO_(2)浓度长期升高条件下冬小麦叶片发生光合适应的机制尚不十分清楚。本研究以盆栽冬小麦‘郑麦9023’为试验材料,在人工气候控制室内设置2个CO_(2)浓度(400和600μmol·mol^(-1))、2个水分条件(田间持水量的80%±5%和55%±5%),测定拔节期和抽穗期的光合特征曲线、叶绿素荧光动力学参数、叶氮含量和收获后的籽粒产量等指标,探讨干旱条件下库源关系改变对叶片光合适应的影响。结果表明:在小麦拔节期,干旱条件下CO_(2)浓度升高处理的小麦PSⅡ实际光化学效率没有显著增加,但通过提升最大电子传递速率和电子向光化学方向的传递比例,增强了Rubisco的羧化速率,从而提高了最大净光合速率;在抽穗期,功能叶最大电子传递速率和电子向光化学方向的传递比例虽然较高,但PSⅡ实际光化学转换效率降低,Rubisco羧化速率和丙糖磷酸利用效率下降,以致最大净光合速率降低。干旱条件下,CO_(2)浓度升高增加了小麦单茎生物量、单穗粒数和穗粒重,降低了不孕小穗数,提高了籽粒产量。土壤干旱条件下,CO_(2)浓度升高对收获期小麦单茎籽粒产量的促进作用可能主要来自于生长前期的光合产物积累。生长后期光合适应发生的主要原因是功能叶PSⅡ实际光化学转换效率和丙糖磷酸利用效率的降低,而不是最大电子传递速率、光化学方向的电子传递比例和新叶库强的变化。

关键词： CO_(2)浓度升高干旱胁迫光合能量分配冬小麦

Identification of novel rodent and shrew orthohepeviruses sheds light on hepatitis E virus evolution

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Zoological Research 2025年第01期 103-121页

作者： Fu-Li Li Bo Wang Pei-yu Han Bei Li hao-Rui Si Yan Zhu Hong-Min Yin Li-Dong Zong Yi Tang Zheng-Li Shi Ben Hu xing-Lou Yang yun-Zhi Zhang Institute of Preventive Medicine School of Public Health Dali University Yunnan Key Laboratory of Screening and Research on Antipathogenic Plant Resources from Western Yunnan Yunnan Key Laboratory of Zoonotic Disease Cross-border Prevention and Quarantine Second People's Hospital of Qujing Programme in Emerging Infectious Diseases Duke-NUS Medical School CAS Key Laboratory of Special Pathogens Wuhan Institute of Virology Chinese Academy of Sciences Key Laboratory of Genetic Evolution & Animal Models Yunnan International Joint Laboratory of Zoonotic Viruses Yunnan Key Laboratory of Biodiversity Information Kunming Institute of Zoology Chinese Academy of Sciences

The family Hepeviridae has seen an explosive expansion in its host range in recent years, yet the evolutionary trajectory of this zoonotic pathogen remains largely unknown. The emergence of rat hepatitis E virus(HEV)has introduced a new public health threat due to its potential for zoonotic transmission. This study investigated2 ?464 wild small mammals spanning four animal orders,eight families, 21 genera, and 37 species in yunnan Province, China. Using broadly reactive reverse transcription-polymerase chain reaction(RT-PCR), we systematically screened the presence and prevalence of Orthohepevirus and identified 192 positive specimens from10 species, corresponding to an overall detection rate of7.79%. Next-generation sequencing enabled the recovery of 24 full-length genomic sequences from eight host species, including Bandicota bengalensis, Eothenomys eleusis, and Episoriculus caudatus, representing newly reported host species for Orthohepevirus *** and sequence analyses revealed extensive genetic diversity within orthohepeviruses infecting rodents and shrews. Notably, among the identified strains, 20 were classified as Rocahepevirus ratti C1, two as C3, and one as Rocahepevirus eothenomi, while the remaining strain exhibited significant divergence, precluding *** analyses highlighted close associations between orthohepeviruses and their respective host taxa,with distinct phylogenetic clustering patterns observed across different host orders. These findings emphasize the critical roles of co-speciation and cross-species transmission in shaping the evolutionary trajectories of the genera Paslahepevirus and Rocahepevirus.

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Phase-matching enhanced quantum phase and amplitude estimation of a two-level system in a squeezed reservoir

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Chinese Physics B 2025年第1期34卷 257-263页

作者： Yan-Ling Li Cai-Hong Liao xing Xiao School of Information Engineering Jiangxi University of Science and TechnologyGanzhou 341000China College of Physics and Electronic Information Gannan Normal UniversityGanzhou 341000China

Squeezed reservoir engineering is a powerful technique in quantum information that combines the features of squeezing and reservoir engineering to create and stabilize non-classical quantum states. In this paper, we focus on the previously neglected aspect of the impact of the squeezing phase on the precision of quantum phase and amplitude estimation based on a simple model of a two-level system(TLS) interacting with a squeezed reservoir. We derive the optimal squeezed phase-matching conditions for phase φ and amplitude θ parameters, which are crucial for enhancing the precision of quantum parameter estimation. The robustness of the squeezing-enhanced quantum Fisher information against departures from these conditions is examined, demonstrating that minor deviations from phase-matching can still result in remarkable precision of estimation. Additionally, we provide a geometric interpretation of the squeezed phase-matching conditions from the classical motion of a TLS on the Bloch sphere. Our research contributes to a deeper understanding of the operational requirements for employing squeezed reservoir engineering to advance quantum parameter estimation.

关键词： quantum parameter estimation squeezed reservoir phase-matching conditions quantum Fisher information

城市绿地降温增湿效应与其结构特征相关性研究

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中国生态农业学报 2008年第6期16卷 1469-1473页

作者：武小钢蔺银鼎闫海冰郝兴宇山西农业大学林学院太谷030801

在太原市区选择2类10个不同结构特征的绿地为研究样本,利用HOBO Pro温、湿度数据采集器对绿地水平和垂直方向上温湿度变化进行测定,研究绿地绿量、叶面积指数、绿地面积、周长面积比4个绿地特征要素与绿地降温增湿效应之间的相关性。结... 详细信息

在太原市区选择2类10个不同结构特征的绿地为研究样本,利用HOBO Pro温、湿度数据采集器对绿地水平和垂直方向上温湿度变化进行测定,研究绿地绿量、叶面积指数、绿地面积、周长面积比4个绿地特征要素与绿地降温增湿效应之间的相关性。结果表明,在水平方向上,绿地降温增湿效应与绿地面积、绿量显著正相关,与绿地周长面积比值显著负相关;在垂直方向上,绿地降温增湿效应与绿量显著正相关,降温效应与叶面积指数显著正相关,增湿效应与叶面积指数正相关性不显著。绿地绿量是衡量绿地生态效益的关键因子,应将其作为绿地系统评价体系的一项重要指标。从城市绿地规划与建设的角度看,在增加绿地面积和提高绿量的同时,一方面要重视大面积斑块的绿地,提高其在绿地系统中的比重,另一方面根据绿地用途相应地选择不同的形状,使城市绿化改善城市生态环境的效应得到充分发挥。

关键词：城市绿地降温增湿效应绿量叶面积指数周长面积比

Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue

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Computers, Materials & Continua 2025年第1期82卷 751-775页

作者： yuewei Wu Ruiling Fu Tongtong xing Fulian Yin College of Information and Communication Engineering Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large *** imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation *** to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction *** can be categorized such as by features and classes,but most studies consider only class *** this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss *** propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature *** network incorporates an attention mechanism and uses multiple sub-networks to classify and learn *** better results,the network can learn the weights of sub-networks and assign higher weights to important *** propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision *** on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods.

关键词： Imbalanced data deep learning e-commerce recommendation loss function big data analysis

Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China(Life Sciences) 2025年第1期68卷 144-157页

作者： Huanbo Zhu Longtao Huangfu Junbing Chen Jiafu Ji Xiaofang xing Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital&InstituteBeijing 100142China Department of Gastrointestinal Cancer Center Peking University Cancer Hospital&InstituteBeijing 100142China Department of Liver Surgery&Transplantation Liver Cancer InstituteZhongshan HospitalFudan UniversityKey Laboratory of Carcinogenesis and Cancer InvasionMinistry of EducationShanghai200032China State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital&InstituteBeijing 100142China

Extrachromosomal DNA(ecDNA)is a form of circular DNA mostly found in tumor *** the typical chromosomal DNA,ecDNA is circular,self-replicating,and carries complete or partial gene *** ecDNA occurrence remains a rare event in cancer,recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer,implying that ecDNA plays a central role in accelerating tumor *** has also been associated with increased tumor mutation burden,chromosomal instability,and even tumor microenvironment *** may be crucial in influencing tumor heterogeneity,drug sensitivity,oncogenic senescence,and tumor immunogenicity,leading to a worsening prognosis for tumor *** this way,several clinical trials have been conducted to investigate the importance of ecDNA in clinical *** this review,we summarize the biogenesis,characteristics,and current research methods of ecDNA,discuss the vital role of ecDNA-caused tumor heterogeneity in cancers,and highlight the potential role of ecDNA in cancer therapy.

关键词： extrachromosomal DNA cancer therapy tumor heterogeneity drug resistance tumor evolution

Metallogenic model of sandstone-hosted copper deposits:a case study from the Paleogene in Jiashi area,northwestern China

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Journal of Palaeogeography 2025年第01期14卷 105-125页

作者： Long-Qing Shi xing-yue Qu Carlos Zavala Yang Li College of Earth Science and Engineering Shandong University of Science and Technology Geology Department Universidad Nacional del Sur Geología de Cuencas Sedimentarias (GCS) Argentina Institute of Energy Peking University Ordos Research Institute of Energy Peking University Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology

Sandstone-hosted copper deposits,a type of Sediment-Hosted Stratiform Copper (SSC) deposits,are widely distributed *** economically viable deposits of SSC are relatively scarce,they account for approximately 30%of the world's total discovered copper ***,there is still a lack of comprehensive and in-depth research into the depositional and metallogenic models of these *** Jiashi area of the Tarim Basin in northwestern China,known for its economically significant Paleogene SSC deposit,lacks in-depth studies on metallogenic *** address this,field profile observations were conducted to analyze the sedimentary evolution,sequence stratigraphy,and tectonism of the Paleogene strata in the Jiashi *** with elemental geochemical analysis of samples,the provenance of sediment,and the source of metallogenic materials,a robust metallogenic model was *** results reveal the influence of provenance for the origin of Paleogene copper-rich *** evolution played a crucial role in controlling the distribution of copper and sulfur elements,as well as the spatial arrangement of metallogenic ***,nappe movement potentially generated faults,allowing upward movement of basin fluids,which played a crucial role in the formation of copper deposits within sandstone-hosted ***,this study offers a comprehensive analysis of the metallogenic processes involved in sandstone-hosted copper deposits,thereby contributing significant insights to the broader research on SSC deposits worldwide.

关键词： Tarim Basin Paleogene Sandstone-hosted copper deposits Metallogenic material source Metallogenic model