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关于求解随机用户均衡问题的截断拟牛顿型信赖域法研究

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数学的实践与认识 2017年第10期47卷 184-190页

作者：刘建美马帅奇济宁学院数学系山东济宁273155

信赖域法是一种保证全局收敛性的优化算法,为避免Hessian矩阵的计算,基于拟牛顿校正公式构造了求解带线性等式约束的非线性规划问题的截断拟牛顿型信赖域法.首先给出了截断拟牛顿型信赖域法的构造过程及具体步骤;然后针对随机用户均衡... 详细信息

信赖域法是一种保证全局收敛性的优化算法,为避免Hessian矩阵的计算,基于拟牛顿校正公式构造了求解带线性等式约束的非线性规划问题的截断拟牛顿型信赖域法.首先给出了截断拟牛顿型信赖域法的构造过程及具体步骤;然后针对随机用户均衡模型中变量和约束的特点对算法进行了修正,并将多种拟牛顿校正公式下所得结果与牛顿型信赖域法的结果进行了比较,结果发现基于对称秩1校正公式的信赖域法更为合适.最后基于数值算例结果得到了一些在算法编程过程中的重要结论,对其它形式信赖域法的编程实现具有一定的参考意义.

关键词：截断拟牛顿公式信赖域法随机用户均衡条件数对称秩1公式

黄土丘陵区生物结皮覆盖对土壤团聚体分布特征及稳定性影响

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土壤通报 2023年第3期54卷 606-613页

作者：张二芳郝旺林马奇美吕梁学院生命科学系山西吕梁033000 中国科学院水利部水土保持研究所陕西杨凌712100 中国科学院大学北京100190

【目的】以吕梁离石区结皮覆盖(藻结皮、藓结皮、藓草混生结皮,裸地为对照)下土壤为研究对象,研究结皮种类对其下层土壤有机碳及土壤团聚体稳定性的影响。【方法】通过干筛和湿筛法对土壤团聚体分级,探究土壤容重、土壤有机碳含量和土... 详细信息

【目的】以吕梁离石区结皮覆盖(藻结皮、藓结皮、藓草混生结皮,裸地为对照)下土壤为研究对象,研究结皮种类对其下层土壤有机碳及土壤团聚体稳定性的影响。【方法】通过干筛和湿筛法对土壤团聚体分级,探究土壤容重、土壤有机碳含量和土壤静水崩解速率与团聚体稳定的相关性。【结果】在0~5 cm和5~10 cm深度,3种结皮下土壤容重与裸地间均达到显著差异;土壤有机碳含量表现为藓草混生结皮和藓结皮分别比裸地显著增加。不同深度土层,团聚体破坏率、分形维数表现为裸地>藻结皮>苔藓结皮>藓草混生结皮;平均重量直径和几何平均直径变化规律正好相反。相关性分析表明,>0.25 mm土壤团聚体含量与土壤容重呈显著负相关关系;团聚体破坏率、分形维数与土壤容重、土壤静水崩解速率呈极显著正相关关系,与土壤有机碳含量呈极显著负相关关系;平均重量直径、几何平均直径与土壤容重呈极显著负相关关系,与土壤静水崩解速率呈显著负相关关系,与土壤有机碳含量呈极显著正相关关系。【结论】黄土丘陵吕梁随结皮层次提高,土壤团聚体形成能力和土壤团聚体水稳定性逐渐增高,对土壤水稳定性起主导作用的是土壤有机碳含量。

关键词：黄土丘陵生物结皮土壤团聚体水稳定性土壤静水崩解速率

1949年以来人文地理学在城市与区域规划中的实践历程与展望

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西华师范大学学报（自然科学版） 2023年第6期44卷 612-621页

作者：税伟麻美琦福州大学地理科学与规划系福建福州350000

1949年以来,从公社规划到农业区划,从县域规划到城市规划,从国内规划走向国外规划,再从区域与城乡规划到今天的国土空间规划体系,人文地理学参与实践了从地方到全球不同尺度和众多类型的规划。本文基于几所典型大学和研究机构的人文地... 详细信息

1949年以来,从公社规划到农业区划,从县域规划到城市规划,从国内规划走向国外规划,再从区域与城乡规划到今天的国土空间规划体系,人文地理学参与实践了从地方到全球不同尺度和众多类型的规划。本文基于几所典型大学和研究机构的人文地理学学科与专业建设和人才培养,在政治、经济、学术和技术发展背景下,梳理了自新中国成立以来人文地理学学科与专业在城市与区域规划实践的发展历程,并将其划分为六个历史阶段。最后面向新时代国土空间规划体系建设的人文地理学学科人才培养进行展望与建议:(1)增强多学科知识融合,提升新技术应用能力;(2)注重宏微观结合,重视多尺度分析与规划;(3)关注全球性问题,更多更广走出国门规划;(4)人才培养方案适应国土空间规划体系建设。

关键词：人文地理学城市与区域规划发展历程国土空间规划人才培养

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie qi Tian Tang Yunfan Zhang Zhiyuan ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 ma cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

Self-assembled carbon monoxide nanoprodrug for chemiexcitationtriggered synergistic chemotherapy against breast cancer

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Science China Chemistry 2025年

作者： Shunfei Cui Yiyao Pan Chenzhe ma Bin qi qingqiang Min Ming Li Huabing Chen Hengte Ke Xingyue Ji Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development College of Pharmaceutical ScienceSoochow University

Carbon monoxide（CO） has recently been well-established as a promising therapeutic modality against cancer. The development of transition-metal-free and tumor-targeted delivery platforms for CO is highly demanded but remains very sporadic. Herein, we developed a polyprodrug system for the co-delivery of CO and a chemotherapeutic agent combretastin A-4（CA-4） to the tumor site based on a chemiexcitation mechanism. Such a poly-prodrug successfully achieved the co-activation of CO and CA-4 in response to H2O2at the tumor site both in vitro and in vivo. Importantly, a synergist effect between CO and CA-4 was observed in suppressing tumor growth in a mouse tumor model. It is anticipated that such a poly-prodrug system could be potentially adapted for the co-delivery of CO and another drug payload for combinational therapy for other indications.

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High-selectivity electroreduction of low-concentration CO2 with large concentration fluctuation

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Science China Chemistry 2025年

作者： Mengyu qi Yanbin ma Chao Zhang Bingwei Li Xueqing Yang Zhaolin Shi Simeng Liu Changhua An Jiqing Jiao Tongbu Lu MOE International Joint Laboratory of materials Microstructure Analysis and Testing CenterInstitute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of Technology Key Laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University

Electrochemical CO2reduction reaction（CO2RR） has been regarded as one of the most promising solutions to achieving “zero carbon emission”. In most of the CO2RR-related studies, high-purity CO2has been employed as the feed gas; however, in practice, CO2is generally emitted in low concentrations, so it is of great significance to realize high-selectivity electroreduction of low-concentration CO2with large concentration fluctuation. In this work, we constructed a dual-active-site catalyst and successfully achieved CO2local enrichment and conversion for low-concentration CO2. Operando experiments reveal that the catalyst has one type of site for activating CO2and one type of site for binding the reaction intermediates. The dual-active-site catalyst displays a selectivity for formic acid consistently above 97% over a broad potential window（from-0.9 to-1.6 V ***）. Even when fed with a low-concentration CO2stream（volume ratio from 50% down to 10%）, the dual-active-site catalyst could display high activity and selectivity（>91%）. In particular, the selectivity is still above 85% when the CO2volume ratio is as low as 5%. This work offers a feasible route for converting low-concentration CO2via a synergistic effect for dual-active-site catalysts.

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maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

基于模糊综合评价的兰州市水生态安全指标体系研究

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干旱区研究 2015年第4期32卷 804-809页

作者：戴文渊张芮成自勇刘静霞马奇梅陈娜娜甘肃农业大学工学院甘肃兰州730070

在对影响城市地区的水生态安全因素深入分析的基础上,以具有代表性的北京、西安、西宁和兰州4个城市为例,从水资源条件与开发利用、水环境与水生态和涉水有关的社会经济等方面,统一选取影响水生态安全的38项指标,构建水生态安全评价指... 详细信息

在对影响城市地区的水生态安全因素深入分析的基础上,以具有代表性的北京、西安、西宁和兰州4个城市为例,从水资源条件与开发利用、水环境与水生态和涉水有关的社会经济等方面,统一选取影响水生态安全的38项指标,构建水生态安全评价指标体系。然后,利用模糊系统分析方法,对指标体系进行优化,最终建立以25项指标组成的兰州市水生态安全评价体系,并用优化后的指标体系对兰州市2009—2013年水生态安全状况进行模糊综合定量评价,找出最主要影响因素。评价结果表明:兰州市水生态安全状况总体趋于好转,但仍受人类生产、生活等活动的影响,部分因素还在威胁兰州市水生态的安全,应引起城建和管理部门重视。最后,对兰州市水生态安全建设方面提出了几点针对性的建议。

关键词：水生态安全模糊综合评价指标体系相关分析兰州

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虚拟护理信息服务系统的设计与实现

复旦学报（医学版） 2005年第1期32卷 59-62页

作者：马琳莫梅琦夏海鸥夏知平徐一新复旦大学医科图书馆上海200032

目的整合网络护理学科信息资源和Internet技术,进行一体化设计建立虚拟护理信息资源服务系统。方法系统采用模块化结构,学科信息资源包括复旦图书馆订购的网络数据库、网上免费护理资源、护理科研人员知识积累。系统平台构架采用We... 详细信息

目的整合网络护理学科信息资源和Internet技术,进行一体化设计建立虚拟护理信息资源服务系统。方法系统采用模块化结构,学科信息资源包括复旦图书馆订购的网络数据库、网上免费护理资源、护理科研人员知识积累。系统平台构架采用Web的多层体系结构Browse Server模式,数据库为SQL Server 2000,开发工具为Jbuilder 9.0。结果系统在一个完整的平台上实现系统管理功能、信息处理功能和通讯功能,具有共享性、安全性、开放性、可扩展等特点。系统实现了护理学科信息资源数字化、一体化、网络化管理。结论建立 "基于学科"的网络信息资源服务平台能够充分有效地利用生物医学网络资源,必将在生物医学领域的临床和研究工作中起到重要作用。

关键词：护理信息护理学科护理资源生物医学领域护理科研临床网上法系重要作用目的