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Enhanced microbial reduction of aqueous hexavalent chromium by Shewanella oneidensis MR-1 with biochar as electron shuttle

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Journal of Environmental Sciences 2022年第3期34卷 12-25页

作者： Cholnam Ri Jingchun Tang Feng Liu Honghong Lyu fengxiang Li College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Processes and Environmental Criteria Ministry of EducationChina Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China Tianjin Key Laboratory of Clean Energy and pollution control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300401China State Academy of Sciences Institute of MicrobiologyPyongyangDemocratic People's Republic of Korea Tianjin Eco-Environmental Comprehensive Support Center Tianjin300191China

Biochar, carbonaceous material produced from biomass pyrolysis, has been demonstrated to have electron transfer property(associated with redox active groups and multi condensed aromatic moiety), and to be also involved in biogeochemical redox reactions. In this study, the enhanced removal of Cr(VI) by Shewanella oneidensis MR-1(MR-1) in the presence of biochars with different pyrolysis temperatures(300 to 800 ℃) was investigated to understand how biochar interacts with Cr(VI) reducing bacteria under anaerobic condition. The promotion effects of biochar(as high as 1.07~1.47 fold) were discovered in this process, of which the synergistic effect of BMBC700(ball milled biochar) and BMBC800 with MR-1 was noticeable, in contrast, the synergistic effect of BMBCs(300–600 ℃) with MR-1 was not recognized. The more enhanced removal effect was observed with the increase of BMBC dosage for BMBC700 + MR-1 group. The conductivity and conjugated O-containing functional groups of BMBC700 particles themselves has been proposed to become a dominant factor for the synergistic action with this strain. And, the smallest negative Zeta potential of BMBC700 and BMBC800 is thought to favor decreasing the distance from microbe than other BMBCs. The results are expected to provide some technical considerations and scientific insight for the optimization of bioreduction by useful microbes combining with biochar composites to be newly developed.

关键词： Sheiuanella oneidensis MR-1 Cr(VI)reduction Biochar Pyrolysis temperature sSynergistic effect

TLR3基因单核苷酸多态性与儿童紫癜性肾炎的相关性

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精准医学杂志 2024年第4期39卷 352-355页

作者：屈凤祥常红林毅青岛大学附属医院儿科山东青岛266003

目的探讨TLR3基因单核苷酸多态性与儿童过敏性紫癜(Henoch-Schönlein purpura,HSP)及紫癜性肾炎(Henoch-Sch nleinöpurpura nephritis,HSPN)易感性的相关性。方法选择HSP患儿174例作为病例组,选择同期体检的162例健康儿童作为对照组。... 详细信息

目的探讨TLR3基因单核苷酸多态性与儿童过敏性紫癜(Henoch-Schönlein purpura,HSP)及紫癜性肾炎(Henoch-Sch nleinöpurpura nephritis,HSPN)易感性的相关性。方法选择HSP患儿174例作为病例组,选择同期体检的162例健康儿童作为对照组。根据病例组患儿在随访过程中是否合并肾脏损害分为HSP组、HSPN组。采用多重聚合酶链反应技术(M-PCR)靶向捕获TLR3基因rs35311343、rs121434431、rs199768900、rs768091235、rs1244010954位点,通过高通量测序技术对所有样本的上述位点进行测序,根据测序结果进行各位点基因型以及基因频率的统计分析。结果病例组与对照组TLR3基因rs35311343、rs121434431、rs199768900、rs768091235、rs1244010954位点的各基因型频率和各等位基因频率比较,差异无显著意义(P>0.05)。病例组中HSP组与HSPN组TLR3基因rs121434431、rs199768900、rs768091235、rs1244010954位点的各基因型频率和各等位基因频率比较,差异无显著性(P>0.05);rs35311343位点的基因型频率与等位基因频率比较差异有显著性(χ^(2)=9.492,OR=2.662,95%CI=1.342~5.281,P<0.05)。结论TLR3基因rs35311343位点CG基因型与儿童过敏性紫癜肾脏受累有关,等位基因G可能是HSPN的易感基因。

关键词：紫癜,过敏性 Toll样受体3 多态性,单核苷酸肾炎高通量核苷酸序列分析儿童

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特高压变压器潜油泵的冲蚀磨损仿真

腐蚀与防护 2024年第4期45卷 69-74页

作者：刘子恩范明豪赵跃陈海鹏苏文马凤翔国网安徽省电力有限公司电力科学研究院合肥230601 浙江大学能源工程学院杭州310027

对潜油泵在工作时的冲蚀和磨损现象开展了数值模拟,计算了不同颗粒粒径、颗粒含量和潜油泵转速下的冲蚀速率。结果表明:主要冲蚀区域集中在叶片上缘,随着金属颗粒尺寸和含量的增加,潜油泵各部件的平均冲蚀率也会增加。此外,在相同冲蚀... 详细信息

对潜油泵在工作时的冲蚀和磨损现象开展了数值模拟,计算了不同颗粒粒径、颗粒含量和潜油泵转速下的冲蚀速率。结果表明:主要冲蚀区域集中在叶片上缘,随着金属颗粒尺寸和含量的增加,潜油泵各部件的平均冲蚀率也会增加。此外,在相同冲蚀条件下,整个叶轮表面的冲蚀分布呈现出不对称性,每个叶片的冲蚀形态和冲蚀速率都具有差异;蜗壳受到冲蚀的区域在周向上的分布角度一般不超过180°。当叶轮转速由900 r/min提高到1500 r/min时,叶轮的平均冲蚀速率会增大6倍。所得结论可为潜油泵的杂质监测设计和故障预警方案提供参考。

关键词：潜油泵冲蚀磨损仿真分析金属颗粒

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老年人驾驶暴露行为影响因素交互作用分析

安全与环境学报 2024年第4期24卷 1523-1530页

作者：郭凤香王猛黄芳熊雪妃蔡晶王晓安昆明理工大学交通工程学院昆明650500 中国汽车工程研究院股份有限公司重庆401122 云南省交通科学研究院有限公司昆明650000

年龄增长带来的身体机能衰退迫使老年人调整驾驶行为,自我调节作为补偿老年人健康状况和降低驾驶风险的策略,能够有效延长驾驶时间和降低驾驶风险。为探究老年人个人生理心理因素和社会环境因素对自我调节中驾驶暴露行为的影响,设计问... 详细信息

年龄增长带来的身体机能衰退迫使老年人调整驾驶行为,自我调节作为补偿老年人健康状况和降低驾驶风险的策略,能够有效延长驾驶时间和降低驾驶风险。为探究老年人个人生理心理因素和社会环境因素对自我调节中驾驶暴露行为的影响,设计问卷并在昆明市开展调查,回收老年人出行调查问卷后对问卷数据进行分析处理,采用Cronbachα信度系数、KMO测度值和验证性因子检验问卷信度效度。统计分析发现,不同年龄段和就业情况的老年驾驶人在驾驶暴露行为上存在显著差异,病史和药物服用会影响老年人驾驶暴露行为,老年人对短距离的频繁出行更有信心。通过构建中介效应分析和结构方程模型探究老年驾驶人驾驶暴露行为影响因素,结果表明:年龄与驾驶暴露行为(r=-0.157^(**),p<0.05)呈显著负相关,驾驶能力与驾驶暴露行为(r=0.182^(**),p<0.05)呈显著正相关;驾驶能力在社会支持和驾驶暴露行为之间起完全中介作用。

关键词：安全工程驾驶暴露影响因素结构方程模型(SEM) 路径分析

Two new species of Mesozoic tree ferns(Osmundaceae:Osmundacaulis)in Eurasia as evidence of long-term geographic isolation

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Geoscience Frontiers 2020年第5期11卷 1875-1888页

作者： Yeming Cheng fengxiang Liu Xiaonan Yang Tongxing Sun Department of Collection Management and Department of Stratigraphy and Paleontology The Geological Museum of ChinaBeijing 100034China School of Marine and Biological Engineering Yancheng Teachers UniversityYancheng 224002China

The fossil trunks and rhizomes of Osmundaceae provide important information about its evolutionary *** to limited records of the Mesozoic trunks and rhizomes in the Eurasia of the Northern Hemisphere,our understanding on the fossil diversity of the Osmundaceae is *** new species of the Osmundaceae trunks,Osmundacaulis asiatica *** Osmundacaulis sinica *** the first discovery of the Mesozoic tree fern genus Osmundacaulis in Eurasia,are described from Wudalianchi and Qiqihar,Heilongjiang Province,Northeast China,which enriches the plant diversity of the Osmundaceae in the Eurasia,and provides vital evidence for studying the distribution,radiation and evolution of the genus during the *** fossil records suggest that Osmundacaulis species may have evolved from a common ancestor,which first appeared in the Australian portion of Pangaea,and then spread to ancient northern North America and ancient East *** then,they developed into different species through their own evolutionary *** Chinese species have a special local feature that the outer cortex is thicker than the inner cortex,in contrast with reported Osmundacaulis species having thinner outer cortex and thicker inner ***-term geographic isolation may have led to the radiation of diverse Osmundacaulis species and the appearance of region-specific features,such as the thick outer cortex and the thin inner cortex of the Chinese *** all reported Osmundacaulis species,the two new species found in China,*** from the Jurassic of Australia and the *** from the Jurassic of the USA,have special groups of mucilage-sacs inside sclerenchyma ring of petiole *** sacs probably originated independently among taxonomic groups,representing convergent adaptations to similar habitats,rather than indicating genetic inheritance from a common ancestor.

关键词： Osmundacaulis Osmundaceae Songliao basin Cretaceous Mucilage sacs Geographic isolation

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均衡相似程度和紧密程度的局部社区发现算法

小型微型计算机系统 2024年第4期45卷 960-967页

作者：张霄宏吴凤祥贾会梅罗军伟河南理工大学计算机科学与技术学院河南焦作454000 河南理工大学软件学院河南焦作454000 河南中光学集团有限公司河南南阳473003

基于局部扩展优化的社区发现方法因能有效揭示网络的社区结构、划分结果稳定等,备受关注.然而在这类方法中,如果种子节点选择不当、社区扩展过程中节点合并不当都会降低划分结果的合理性.此外,由于采用贪婪的扩展策略,其收敛速度受到了... 详细信息

基于局部扩展优化的社区发现方法因能有效揭示网络的社区结构、划分结果稳定等,备受关注.然而在这类方法中,如果种子节点选择不当、社区扩展过程中节点合并不当都会降低划分结果的合理性.此外,由于采用贪婪的扩展策略,其收敛速度受到了制约.针对以上问题,提出了均衡相似程度和紧密程度的局部社区发现算法.该算法利用节点间的相似程度和连接紧密程度构建种子社区,从种子社区出发以迭代的方式进行扩展直至收敛;在社区扩展过程中引入了一种两级筛选机制,利用该机制将在相似程度和连接紧密程度两方面优势均衡的多个节点合并到当前社区.通过构建种子社区和引入两级筛选机制提高社区划分结果的合理性.在社区扩展过程中引入合并策略,以优化算法收敛速度.在多个数据集上的对比实验证明了本文方法的正确性和有效性.

关键词：社区发现社区扩展局部社区发现相似程度紧密程度

Facile fabrication of amphoteric semi-interpenetrating network membranes for vanadium flow battery applications

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Journal of Energy Chemistry 2018年第4期27卷 1189-1197页

作者： Ruijun Gan Yanjiao Ma Shanshan Li fengxiang Zhang Gaohong He State Key Laboratory of Fine Chemicals School of Chemical and Petroleum Engineering Dalian University of Technology

For improvement of vanadium redox flow battery （VRB） performance, novel amphoteric semi- interpenetrating membranes （ASIPN） were prepared using poly（ether ether ketone）（PEEK） and polysul- fone （PSf）, the former bearing sulfonic groups and the latter imidazolium. These two groups form ionic crosslinks between PEEK and PSf; meanwhile, covalent cross links were built between PSf chains with ad- dition of N-（3-aminopropyl）-imidazole. The amphoteric nature of the membrane allows facile proton and anion transport; the IPN structure and the presence of imidazolium cation effectively suppress vanadium ion crossover through the membrane. Therefore, the ASIPN based VRBs show higher Coulombic efficiency and energy efficiency than that assembled with pristine SPEEK and Nation 212 membranes. Our work demonstrates that the ASIPN membranes are promising for VRB applications.

关键词： Vanadium redox flow battery ASIPN Cross-linking Amphoteric membrane

张吉怀铁路酉水大桥非对称拱桥钢拱肋架设技术研究

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高速铁路技术 2024年第2期15卷 102-107,118页

作者：孙凤祥左少群李江中铁大桥局集团第五工程有限公司江西九江332001

张吉怀铁路酉水大桥主桥为主跨292 m的非对称上承式钢管混凝土拱桥,其钢拱肋采用斜拉扣挂法进行节段悬臂架设施工。本文结合张吉怀铁路酉水大桥工程,针对高速铁路非对称拱桥钢拱肋安装施工技术展开研究,主要包括:复杂地形条件下的施工技... 详细信息

张吉怀铁路酉水大桥主桥为主跨292 m的非对称上承式钢管混凝土拱桥,其钢拱肋采用斜拉扣挂法进行节段悬臂架设施工。本文结合张吉怀铁路酉水大桥工程,针对高速铁路非对称拱桥钢拱肋安装施工技术展开研究,主要包括:复杂地形条件下的施工技术,因地制宜地进行缆索起重机的设计及安装,钢管拱整节段拼装和架设,合龙装置和技术等。该施工技术保障了钢拱肋架设的精度和质量,钢拱肋的成拱线形与设计值较为吻合。该桥运营以来,各结构性能指标均满足设计要求。

关键词：张吉怀铁路酉水大桥非对称钢管混凝土拱桥钢拱肋斜拉扣挂法施工技术

SHRIMP Age of Exotic Zircons in the Mengyin Kimberlite,Shandong,and Their Formation

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Acta Geologica Sinica(English Edition) 2005年第5期79卷 654-661页

作者： YIN Zuowei LU fengxiang CHEN Meihua Gemmological Institute China University of Geosciences Wuhan Hubei 430074 Earth Science Department China University of Geosciences Wuhan Hubei 430074

Due to various courses of formation of zircons from kimbedites, different kinds of zircons can provide useful information about the mantle and the crystallization of kimberlites. We chose 9 typical ones out of 33 zircons from the Shengli- 1 kimberlite pipe in Mengyin County, Shandong Province to study their ages and formation by means of SHRIMP, CL, Raman spectroscopy, etc. The result shows that the ^207Pb/^206Pb ages of many zircons vary from 2567±13 Ma to 2636±42 Ma, which are close to the age of Archaean granitoid （2457.3±47 Ma） in the study area. The contents of U and Th in the samples are higher than those of zircons crystallized in kimbedite and vary from 89 to 398 ppm as well as from 10 to 283 ppm. Color zones are obvious in these samples under the CL. The inclusions are composed of feldspar, quartz, apatite, etc. The above results show that the zircon samples came from the crust of the earth, which means that the kimberlite magmas are contaminated by crustal substances. The position where a great deal of volatile escapes and even explodes during rapid rise of magmas is located at the boundary of the ancient basement and the Precambrian stratum.

关键词： kimberlite exotic zircons ages SHRIMP contamination Shandong