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Rare Metals 2024年第2期43卷 612-623页

作者： Jia Luo shi-li xiang Dan-Yang Han An liu João Cunha Gang-Yong li Zhao-Hui Hou Hong Yin School of Chemistry and Chemical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional MaterialsHunan Institute of Science and TechnologyYueyang414006China Hubei Jiufengshan Laboratory Wuhan430206China International Iberian Nanotechnology Laboratory(INL) Av.Mestre Jose Veiga4715-330BragaPortugal

Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(liBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during li/Na-ion intercalation significantly impairing the li/Na-storage ***,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal *** unique structure can facilitate the properties of reactivity,conductivity and ionic *** addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural *** synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling *** N-DC@(CoSn)S anode delivers enhanced high specific capacities of 820.6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for liBs and 339.2 mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,*** work is expected to provide a material design idea for preparing liBs/SIBs with high capacity and long cycling life.

关键词： Interface engineering Long chain heterostructure High capacity Cycling stability li Na-ion batteries

Salmon calcitonin in prevention of osteoporosis in maintenance dialysis patients

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Chinese Medical Journal 2008年第14期121卷 1280-1284页

作者： WANG shi-xiang li Han Blood Purification Center Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Background Renal osteodystrophy is one of the commonest complications of chronic renal failure. It may have a severe impact on the quality of life of patients on maintenance dialysis therapy. Besides post-menopausal women and elderly people, the dialysis patients are another high risk group. But at present, there is no research on how to prevent osteoporosis in maintenance dialysis patients. This study was conducted to observe the bone density of maintenance dialysis patients and to evaluate the clinical outcomes and safety of different administration dosage of salmon calcitonin to prevent osteoporosis in maintenance dialysis patients. Methods One hundred and forty-eight patients on maintenance dialysis were involved in the 12-month, randomized, controlled trial. Fifty patients （experiment I group） received subcutaneous injection of salmon calcitonin （50 U） three times a week for 12 months. Fifty patients （experiment II group） received subcutaneous injection of salmon calcitonin （100 U） three times a week for 12 months. At the same time, both of them received oral calcium carbonate 1500 mg tid and rocaltrol 0.25 pg qn for 12 months. The control group only received oral calcium carbonate 1500 mg tid and rocaltrol 0.25 μg qn for 12 months. The levels of bone mass density （BMD） of the lumbar spine and femoral neck, serum intact parathyroid hormone （iPTH）, osteocalcin （OC）, calcium, phosphorus, alkaline phosphatase （ALP） were assessed at baseline and then again after 3, 6 and 12 months of treatment. Results The values of BMD at the lumbar spine and femoral neck before the treatment were not significantly different from those 3, 6, and 12 months after the treatment in trial groups I and II （all P 〉0.05） and there were no significant differences in the BMD values at different time points between trial groups I and II. In the control group, the BMD values at the lumbar spine and femoral neck 3, 6, and 12 months after the beginning of trial were significantly lower than

关键词： dialysis oestoporosis bone mass density salmon calcitonin

A NEW METHOD FOR PREDICTION OF PRODUCTIVITY OF FRACTURED HORIZONTAL WELLS BASED ON NON-STEADY FLOW

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Journal of Hydrodynamics 2007年第4期19卷 494-500页

作者： LEI Zheng-dong CHENG shi-qing li xiang-fang XIAO Hua-ping Research Institute of Petroleum Exploration and Development Beijing 100083 China CMOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249China BeiJing Huayou Natural Gas Co. Itd Beijing 100100 China

Hydraulic fracturing technologies of horizontal well are important ways to develop oil-gas field with low permeability. Productivity forecast of fractured horizontal wells is a difficult problem of hydraulic fracturing technologies. Basing on non-steady flow of fractures fluid during production, applying potential function principles, superposition principle and mathematical method for solving, coupling of seepage flow in the formation and pipe flow in the well bore, a new model on multi-fracture interference productivity forecast of fractured horizofltal well is established in this article. The results indicate the coincidence rate between this model and practice is high. The pressure loss in the horizontal well bore has definite influence on the production status of fractured horizontal wells. The productions of different fractures in horizontal well bore are unequal, the productions of outer fractures are higher than middle fractures; the pressure in the well bore shows an uneven distribution, the pressure declines gradually from finger tip to heel end. Asymmetry of fractures may make productivity of fractured horizontal wells decline. The conclusions are instructive in designing fractured horizontal well for low permeability reservoir.

关键词： horizontal well fracturing productivity couple non-steady flow

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： xiang-Qun Fu Hong-Wei li Jian-Hong shi Tan li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu Yantong li Meng-xiang Wu Hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

高校图书馆读者网上荐购的现状与思考——基于对50所高校的调查

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图书馆论坛 2013年第5期33卷 117-122页

作者：史丽香南开大学图书馆天津300071

为分析高校图书馆读者网上荐购现状,选取50所高校进行调查。读者网上荐购已成为高校图书馆常规服务手段,但存在不足:书目信息不完善、对读者荐购的反馈不及时、读者参与荐购的方式不完善。图书馆应提供全面的分类书目,提供更多样更完善... 详细信息

为分析高校图书馆读者网上荐购现状,选取50所高校进行调查。读者网上荐购已成为高校图书馆常规服务手段,但存在不足:书目信息不完善、对读者荐购的反馈不及时、读者参与荐购的方式不完善。图书馆应提供全面的分类书目,提供更多样更完善的荐购途径,重视读者反馈,建立荐购人信息档案,以提高荐购服务水平。

关键词：高校图书馆读者网上荐购荐购系统

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： shi Yuqiong li Jingyi ZHANG Yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

基于工业化视角的能源效率评价方法与实证研究

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中国人口·资源与环境 2010年第11期20卷 12-18页

作者：李世祥中国地质大学(武汉)国土资源法律评价工程实验室湖北武汉430074 中国社会科学院数量经济与技术经济研究所北京100732

节能减排潜力的准确评估依赖于对能源效率的科学评价,而能源效率评价又涉及到能源与经济发展的关系问题。20世纪90年代以来,中国的工业化一直处于快速推进阶段,对能源依赖较强的高耗能行业成为经济增长的主要推动力。因此,中国工业化进... 详细信息

节能减排潜力的准确评估依赖于对能源效率的科学评价,而能源效率评价又涉及到能源与经济发展的关系问题。20世纪90年代以来,中国的工业化一直处于快速推进阶段,对能源依赖较强的高耗能行业成为经济增长的主要推动力。因此,中国工业化进程中的能源效率评价必须结合工业化背景下的经济增长理论与实践。与单要素能源效率方法相比,全要素能源效率方法及多目标情形下的能源效率评价模型是评价工业化经济体能源效率的一个较好分析框架。该分析框架以工业化、经济增长为背景,以生产函数为依托,不仅可以比较准确地衡量重要经济变量不断变化条件下能源与其他要素之间的替代效应,而且可以反映出一个国家或地区在特定经济发展阶段、要素禀赋结构以及经济激励机制下能源使用的综合水平,使评价结果更符合中国正处于工业化过程的经济现实。在该分析框架的基础上,结合工业行业面板数据,对中国工业部门的能源效率进行了实证测算。

关键词：节能减排工业化全要素能源效率中国工业部门

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中国工业化进程中的能耗特征及能效提升途径

中国软科学 2010年第7期 23-35页

作者：李世祥中国地质大学(武汉)国土资源法律评价工程实验室湖北武汉430074 中国社会科学院数量经济与技术经济研究所北京100732

本文提出要在工业化背景下理解中国的能源消耗与节能减排,并着重分析了中国工业化进程中的能耗特征及能效提升途径。研究结果表明,20世纪后20年期间,中国以低能耗支撑了经济高增长,但这只是暂时现象,是由多种非结构性因素综合作用的结... 详细信息

本文提出要在工业化背景下理解中国的能源消耗与节能减排,并着重分析了中国工业化进程中的能耗特征及能效提升途径。研究结果表明,20世纪后20年期间,中国以低能耗支撑了经济高增长,但这只是暂时现象,是由多种非结构性因素综合作用的结果。而进入新世纪以来,中国的单位GDP能耗呈现上升趋势,这与工业化进程的加速有关。从长期来看,中国工业化进程中的能源消耗仍将遵循工业化中能源消耗的一般规律。未来中国能源效率提升的政策途径应该从产业结构、能源结构、技术进步、能源价格、区域经济、能源资源合理开发利用等多方面展开。

关键词：能源消耗特征能源效率工业化中国