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低温下装配式建筑层间结构脆弱点检测与仿真

计算机仿真 2024年第8期41卷 326-330页

作者：廖菲菲徐理张玉清新余学院建筑工程学院江西新余338004 世纪大学工程建筑环境和信息技术学院马来西亚哥打白沙罗47810

装配式建筑的层间结构通常由大量的连接件、悬挂系统和焊接点组成,脆弱点通常位于这些连接部位。在低温环境下,由于结构的复杂性,有些脆弱点难以被直接检测到。因此,提出低温环境装配式建筑层间结构脆弱点检测仿真。利用红外线热成像法... 详细信息

装配式建筑的层间结构通常由大量的连接件、悬挂系统和焊接点组成,脆弱点通常位于这些连接部位。在低温环境下,由于结构的复杂性,有些脆弱点难以被直接检测到。因此,提出低温环境装配式建筑层间结构脆弱点检测仿真。利用红外线热成像法获取建筑物外墙保温结构,分析房屋热传导过程。研究外侧层间结构中脆弱点堆积热量情况,叠加检测时段,利用导热微分方程获取红外边值条件,明确层间结构的热传导和时间变量,计算墙体结构的内外导热热阻,判断外侧层间结构缺陷位置。构建建筑层间结构脆弱点的评估框架,整合脆弱点评价值,通过决策单元自我评价,在线性规划结果中获得最优解,根据交叉评价值完成内部层间结构脆弱点检测结果。经过实验证明,研究方法能有效检测出装配式建筑内外层间结构的脆弱点,方法鲁棒性好,实用性强。

关键词：低温环境脆弱性评价装配式建筑层间结构红外热成像法

建筑管道直饮水系统臭氧衰减模型及生产运行调控

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中国给水排水 2024年第15期40卷 9-15页

作者：柯水洲张春雨欧阳林陶策陈佳黎思云湖南大学土木工程学院湖南长沙410082 长沙水思源产业发展有限公司湖南长沙410017

为优化臭氧消毒工艺和确保管道直饮水安全,以正在运行的管道直饮水系统作为研究基地,进行了臭氧浓度衰减静态和动态试验。在净水箱中臭氧浓度随时间的衰减符合二项式拟合曲线,半衰期约为30~45 min;当净水箱中臭氧初始浓度分别为0.06、0... 详细信息

为优化臭氧消毒工艺和确保管道直饮水安全,以正在运行的管道直饮水系统作为研究基地,进行了臭氧浓度衰减静态和动态试验。在净水箱中臭氧浓度随时间的衰减符合二项式拟合曲线,半衰期约为30~45 min;当净水箱中臭氧初始浓度分别为0.06、0.12、0.18 mg/L时,静置120 min后臭氧残留浓度均在0.01 mg/L以上。净水箱中臭氧投加量分别为0.06、0.12、0.18 mg/L时,在不循环、不出水工况下,用水点的臭氧浓度先随时间增加而增加,一段时间后开始下降,150 min后均小于0.01 mg/L;在出水、不循环工况下,随着出水流量或臭氧投加量的增加,用水点的臭氧浓度降低到0.01 mg/L以下所需时间相应增加;开启循环后,出水流量越大或臭氧投加量越大,末端臭氧浓度达到0.01 mg/L所需时间越短。循环消毒制度优化试验表明,对菌落总数和铜绿假单胞菌检出的影响程度为臭氧投加量>每日循环次数>每次循环时间。当臭氧投加量达到0.13~0.18 mg/L、每日循环8次、每次循环15 min时,可以确保用水点检测到的铜绿假单胞菌数基本为0。

关键词：管道直饮水臭氧衰减铜绿假单胞菌循环消毒正交优化

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紫河车冻干粉改善睡眠作用及机制研究

药物评价研究 2024年第2期47卷 316-322页

作者：车云任季禹韩聪黄绍菊张云臧传宝张姗姗付开玲刘可春夏青陕西城固县医院妇产科陕西汉中723200 银丰低温医学科技有限公司山东济南250000 山东省科学院生物研究所山东济南250013 单县妇幼保健计划生育服务中心山东菏泽274300

目的研究紫河车冻干粉改善睡眠的作用及机制。方法利用ip氯苯丙氨酸(PCPA)法制备大鼠失眠模型,设置对照组、模型组和紫河车冻干粉低、中、高剂量(0.09、0.18、0.36 g·kg^(-1))组,每天ig给药1次,连续给药7 d,对照组和模型组ig等量去离... 详细信息

目的研究紫河车冻干粉改善睡眠的作用及机制。方法利用ip氯苯丙氨酸(PCPA)法制备大鼠失眠模型,设置对照组、模型组和紫河车冻干粉低、中、高剂量(0.09、0.18、0.36 g·kg^(-1))组,每天ig给药1次,连续给药7 d,对照组和模型组ig等量去离子水。通过检测体质量增长量、一般观察、翻正实验、旷场实验、强迫游泳实验、悬尾实验评价紫河车冻干粉改善睡眠的作用;利用Western blotting技术检测γ-氨基丁酸转氨酶(GABA-T)、谷氨酸脱羧酶-65(GAD65)、γ-氨基丁酸转运体1(GAT1)蛋白的表达水平。结果与模型组比较,紫河车冻干粉低、中、高剂量组大鼠体质量增加量显著升高(P<0.01);中、高剂量紫河车冻干粉具有显著缩短睡眠潜伏期(P<0.05)、显著延长睡眠时间(P<0.01)的作用;高剂量紫河车冻干粉使大鼠中央格停留时间显著延长(P<0.01)、中央格穿格次数显著增多(P<0.05)、站立次数和修饰次数显著增多(P<0.01),说明高剂量紫河车冻干粉能够减轻失眠大鼠焦虑情绪,增强自发探索活动能力;高剂量紫河车冻干粉使大鼠漂浮时间缩短(P<0.05),挣扎时间延长(P<0.01),说明高剂量紫河车冻干粉能够减轻失眠大鼠的抑郁状态。Western blotting结果显示,与模型组相比,紫河车冻干粉处理组大鼠下丘脑组织中GABA-T的表达水平显著降低(P<0.05),GAD65、GAT-1的表达水平显著升高(P<0.05、0.01)。结论紫河车冻干粉可能通过调控GABA-T、GAD65、GAT-1蛋白的表达水平,发挥改善睡眠的作用。

关键词：紫河车冻干粉改善睡眠蛋白免疫印迹 GABA能系统通路作用机制

The mechanism of unexpected reduction of dimethyl pyridine-2,3-dicarboxylate to l,2,3,4-tetrahydrofuro[3,4-b]-pyridin-5(7H)-one with sodium borohydride

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Chinese Chemical Letters 2012年第10期23卷 1122-1124页

作者： Yan Bo Tang qing Jian zhang De Quan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

An unexpected reduction of dimethyl pyridine-2,3-dicarboxylate to 1,2,3,4-tetrahydrofuro[3,4-b]pyridin-5（7H）-one with sodium borohydride in ethanol and tetrahydrofuran, respectively, is described, a hypothetic mecha... 详细信息

关键词： Reduction Sodium borohydride Dimethyl pyridine-2,3-dicarboxylate 1,2,3,4-Tetrahydrofuro[3,4-b]pyridin-5(7H)-one Reactionmechanism

Urban Spatial Restructuring in Transitional Economy——Changing Land Use Pattern in Shanghai

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Chinese Geographical Science 2007年第1期17卷 19-27页

作者： XU Jiangang LIAO Banggu SHEN qing zhang Feng MEI Anxin Department of Urban and Resources Sciences Nanjing University Nanjing 210093 China Urban Studies and Planning Program University of Maryland College Park MD 20742 USA Department of Geography East China Normal University Shanghai 200062 China

For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- sources allocation, have caused profound spatial restructuring of Chinese cities. This paper examines urban expansion and land use reconfiguration in Shanghai’s central city from 1979 to 2002, with a special focus on the effect of the adoption of the land-leasing system in 1988. The empirical research, which employs GIS-based spatial analysis tech- niques to explore land use data for multiple years, indicates fundamental changes in the spatial characteristics of urban development in Shanghai after this important land policy reform.

关键词： land use pattern land policy GIS Shanghai China

原发全面强直阵挛型癫痫合并睡眠障碍患者的脑血流灌注特点

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中国神经免疫学和神经病学杂志 2024年第1期31卷 8-12页

作者：陈秋艳李梦云张庆宁夏医科大学临床医学院 750000 宁夏医科大学总医院神经内科 750000

目的研究原发全面强直阵挛型癫痫(idiopathic generalized epilepsy with generalized tonic-colonic seizure,IGE-GTCS)合并睡眠障碍患者及未合并睡眠障碍IGE-GTCS患者的脑血流灌注特点。方法收集2021年12月至2022年12月就诊于宁夏医科大学总医院神经内科癫痫门诊并诊断为IGE-GTCS患者62例。根据有无睡眠障碍将患者分为IGE-GTCS合并睡眠障碍组和IGE-GTCS未合并睡眠障碍组。另收集年龄、性别、受教育程度与病例组相匹配、接受颅脑CT或磁共振检查的体检者及其他无神经系统疾病患者16名纳入对照组。采用手动勾画方法检测3组受试者脑部不同部位感兴趣区(region of interest,ROI)的脑血流量(cerebral blood flow,CBF)差异。结果IGE-GTCS合并睡眠障碍组、未合并睡眠障碍组及对照组左侧额叶、左侧丘脑及左侧海马结构CBF比较差异有统计学意义(均P<0.05)。两两比较结果显示,与对照组比较,IGE-GTCS合并睡眠障碍组左侧额叶、左侧丘脑及左侧海马ROI CBF降低(均P<0.05),未合并睡眠障碍组左侧额叶、左侧丘脑ROI CBF降低(均P<0.05);与IGE-GTCS未合并睡眠障碍组比较,合并睡眠障碍组左侧海马结构ROI CBF减少(P<0.05)。结论IGE-GTCS合并睡眠障碍患者及未合并睡眠障碍患者CBF异常存在差异,这将有助于进一步从脑功能角度理解IGE-GTCS合并睡眠障碍的病理生理机制。

关键词：原发全面强直阵挛型癫痫睡眠障碍三维伪连续式动脉自旋标记成像技术脑血流量

Correlation and interaction between temperature and freeze-thaw in representative regions of Antarctica

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International Journal of Digital Earth 2022年第1期15卷 2296-2318页

作者： Dong Liang Huadong Guo qing Cheng Lu zhang Lingyi Kong Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China International Research Center of Big Data for Sustainable Development Goals BeijingPeople’s Republic of China School of Computer Science China University of GeoscienceWuhanPeople’s Republic of China

As the most sensitive and direct indicator of global climate change,the freezing and thawing of the Antarctic ice sheet is of great significance for research on surface mass and energy *** this study,four representative regions in Antarctica were selected and correlation analysis,Granger causality testing,and cluster analysis were applied to comprehensively analyze the correlation and response of spatiotemporal variation in freeze-thaw and *** conclusions are as follows.(1)In the Antarctic Peninsula,a phenomenon was demonstrated that the summer shifts *** December and colder March temperatures were observed in the Amery Ice Shelf and Queen Maud Land.(2)The Antarctic Peninsula featured the most severe degree of melting among the four regions,with the largest melt area in the past 30 years appearing during the 2015/2016 ***,the number of melt days in most areas of the Antarctic Peninsula was observed to have decreased.(3)There is a strong correlation between the freeze-thaw state of the Antarctic ice sheet and temperature,as well as spatial differences among regions,but the data were clustered at different time scales.

关键词： Antarctic ice sheet Big Earth Data freeze-thaw microwave remote sensing snowmelt temperature

Effects of Vertex Activity and Self-organized Criticality Behavior on a Weighted Evolving Network

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Communications in Theoretical Physics 2008年第8期50卷 421-424页

作者： zhang Gui-qing YANG Qiu-Ying CHEN Tian-Lun Department of Physics Nankai University Tianjin 300071 China

Effects of vertex activity have been analyzed on a weighted evolving *** network is characterized by the probability distribution of vertex strength,each edge weight and evolution of the strength of vertices with different vertex *** model exhibits self-organized criticality *** probability distribution of avalanche size for different network sizes is also *** addition,there is a power law relation between the size and the duration of an avalanche and the average of avalanche size has been studied for different vertex activities.

关键词： weighted evolving network vertex activity power-law self-organized criticality

Efficient strategies for changing the diapause character of silkworm eggs and for the germline transformation of diapause silkworm strains

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Insect Science 2012年第2期19卷 172-182页

作者： Ai-chun Zhao Ding-Pei Long San-Yuan Ma Long-Xia Xu Mei-Rong zhang Fang-Yin Dai qing-You Xia Cheng Lu Zhong-Huai Xiang The Key Sericultural Laboratory of Agricultural Ministry Institute of Sericulture and Systems BiologySouthwest UniversityChongqingChina

To overcome the disadvantages of current silkworm Bombyx mori transgenic technology, such as costly and time-consuming to maintain non-diapause transgenic silkworms, we report here on the development of treatments for the germline transformation of diapause silkworm strains. Our results showed that HC1 treatment within 3 h of oviposition was able to prevent the diapause of eggs from Japanese lineage diapause silkworm strains and was also suitable for germline transformation of the same strains. By incu- bating developing mother eggs from Chinese lineage diapause silkworm strains at 15℃ （15℃-IME）, we were able to prevent the diapause of their daughter eggs; a similar strategy （15℃-IMES） for the germline transformation of the same strains was that the mother eggs were incubated at 15℃, and the daughter eggs were then microinjected according to the conventional microinjection methods used for non-diapause eggs. By combining tempera- ture and light controls, the improved 15℃-IMES strategy prevented diapause in daughter eggs, and also enabled the germline transformation of both Japanese and Chinese lineage diapause silkworm strains. Although each of the strategies developed here has advantages and disadvantages, we suggest that the 15℃-IMES strategy is a good reference for the establishment of germline transformation technologies of other egg diapause insects. These new strategies for the efficient germline transformation of diapause silkworm strains are likely to improve the practical use of silkworm transgenic lines in sericulture and also highlight silkworm functional genomics research and its modeling.

关键词： Bombyx mori diapause functional genomics gerrnline transformation insect piggyBac