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基于水化热抑制剂的大体积混凝土温控技术

科学技术与工程 2024年第19期24卷 8227-8238页

作者：杨益波郭智渊韩炜王子意朱劲松中交一公局集团有限公司北京100024 天津大学建筑工程学院天津300072

为完善现有大体积混凝土水化温升控制技术,并通过合理应用抑制剂温控措施来降低施工成本,基于水泥水化绝热温升曲线,提出了一种调节绝热温升方程中延迟放热时间的模型,进而控制混凝土掺入不同抑制剂的绝热温升过程。研究结果表明:延迟... 详细信息

为完善现有大体积混凝土水化温升控制技术,并通过合理应用抑制剂温控措施来降低施工成本,基于水泥水化绝热温升曲线,提出了一种调节绝热温升方程中延迟放热时间的模型,进而控制混凝土掺入不同抑制剂的绝热温升过程。研究结果表明:延迟放热时间为0~3 d时,大体积混凝土内部温峰和内表温差呈不断减小的趋势;而在延迟放热时间为5~10 d时,由于延迟放热时间的增加,会导致多层浇筑混凝土的热量积蓄;选用延迟放热时间为3 d的浇筑混凝土,其温峰与内表温差均能达到温控目标;对于延迟放热时间为1 d的浇筑混凝土,若能将入模温度降低1~2℃,也能满足温控要求;本研究所提出的基于水化热抑制剂的混凝土温升调控技术,为大体积混凝土水化热温度场的调控提供了新的思路和方法。

关键词：大体积混凝土水化热抑制剂绝热温升温度控制数值模拟

Research and development of advanced structured packing in a rotating packed bed

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Chinese Journal of Chemical Engineering 2022年第9期35卷 178-186页

作者： zhi-guo yuan Yu-Xia Wang You-zhi Liu Dan Wang Wei-Zhou Jiao Peng-Fei Liang Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

As the core component of the rotating packing bed,packing is a place for efficient gas–liquid mixing and mass *** this paper,a 3D structured packing composed of a mesh structure and a support structure was *** mesh structure is a ring-shaped mesh surrounded by triangular meshes,which is stable in structure and can achieve a high degree of dispersion and aggregation of the liquid *** support structure is composed of ring-shaped structural units arranged at a certain angle along the axial direction,which can enhance the turbulence of the airflow while constructing regular gas-phase *** steel meshes of different diameters and supporting structures are alternately combined to form 3D packing,which is loaded in a layered cross-flow rotating packing *** results show that under the same operating conditions,the mass transfer performance of 3D packing and wire mesh packing are equivalent,and both are better than pall ring ***,the pressure drop of 3D packing is significantly lower than that of pall ring packing and wire mesh *** design and implementation of packing the development presented in this paper can be used to develop special structured packing for rotating bed,which can further improve the performance of rotating packed bed(RPB).

关键词： Rotating packed bed 3D printed packing 3D modeling Mass transfer Pressure drop Gas–liquid channel

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大跨度网状吊杆系杆拱桥关键节点设计

公路 2024年第8期69卷 5-9页

作者：王宇锋吴霄郭智渊陈晨陶星张玲玲济南城市建设集团有限公司济南市250000 上海市政工程设计研究总院(集团)有限公司上海市200092 济南市政公用资产管理运营有限公司济南市250000 山东易方达建设项目管理有限公司济南市250000

齐鲁黄河大桥为(95 m+280 m)+420 m+(280 m+95 m)多跨下承式网状吊杆拱桥,其拱肋内倾,采用五边形钢箱断面,主梁采用正交异性组合桥面板组合梁。复杂的断面形式以及拱肋空间曲线的变化导致大桥拱脚连接构造异于传统拱梁组合体系,传力路... 详细信息

齐鲁黄河大桥为(95 m+280 m)+420 m+(280 m+95 m)多跨下承式网状吊杆拱桥,其拱肋内倾,采用五边形钢箱断面,主梁采用正交异性组合桥面板组合梁。复杂的断面形式以及拱肋空间曲线的变化导致大桥拱脚连接构造异于传统拱梁组合体系,传力路径复杂,为此对该类异形拱肋拱梁节点进行详细设计,并利用空间有限元模型对该部位构造进行验算。计算结果表明,所设计的拱梁节点构造能够保证传力的顺畅与可靠,除局部存在应力集中现象外,主要受力板件应力均满足设计要求。

关键词：桥梁工程齐鲁黄河大桥网状系杆拱桥拱梁节点异形拱桥组合拱桥

Human umbilical cord mesenchymal stem cells promote peripheral nerve repair via paracrine mechanisms

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Neural Regeneration Research 2015年第4期10卷 651-658页

作者： zhi-yuan guo Xun Sun Xiao-long Xu Qing Zhao Jiang Peng Yu Wang Institute of Orthopedics Chinese PLA General Hospital The Neural Regeneration Co-innovation Center of Jiangsu Province

Human umbilical cord-derived mesenchymal stem cells （hUCMSCs） represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the para-crine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These ifndings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

关键词： nerve regeneration human umbilical cord-derived mesenchymal stem cells conditioned medium Schwann cells dorsal root ganglion axons peripheral nerve regeneration neurotrophic factors neural regeneration

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茶营养健康作用的系统评价研究论述

茶叶学报 2024年第1期65卷 67-82页

作者：和智坚李毓萍卜凡崔佳毕馨文崔远捷郭智源李鸣四川大学华西公共卫生学院/华西第四医院四川成都610041 华西第二医院临床营养科四川成都610041 四川省人民医院临床营养科四川成都610072 宜宾市第二人民医院临床营养科四川宜宾644000

茶作为一种传统的营养健康经济作物,具有降低心血管、肥胖、糖尿病等慢性疾病风险,以及调节和促进人体健康水平的积极作用。近几十年来,有关茶营养健康作用探究的动物及人群试验数量成果丰硕,但基于试验数据分析归纳的系统评价研究结果... 详细信息

茶作为一种传统的营养健康经济作物,具有降低心血管、肥胖、糖尿病等慢性疾病风险,以及调节和促进人体健康水平的积极作用。近几十年来,有关茶营养健康作用探究的动物及人群试验数量成果丰硕,但基于试验数据分析归纳的系统评价研究结果还不够深入和全面。因此,文章系统回顾并评价近十年茶营养健康作用探究的人群干预试验,以综述的方式归纳茶的各项营养健康作用。结果显示,茶在抗氧化作用、调节血压血脂、降低血糖水平、预防超重与肥胖及免疫调节等方面具有良好的健康效益,说明茶在预防心血管疾病、调节和控制糖脂代谢性疾病发生及维持机体正常免疫水平方面发挥着积极作用。

关键词：茶营养健康作用系统评价研究论述

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Extracellular matrix from human umbilical cordderived mesenchymal stem cells as a scaffold for peripheral nerve regeneration

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Neural Regeneration Research 2016年第7期11卷 1172-1179页

作者： Bo Xiao Feng Rao zhi-yuan guo Xun Sun Yi-guo Wang Shu-yun Liu Ai-yuan Wang Quan-yi guo Hao-ye Meng Qing Zhao Jiang Peng Yu Wang Shi-bi Lu Institute of Orthopedics Chinese PLA General HospitalBeijingChina Beijing Key Laboratory of Regenerative Medicine in Orthopedics BeijingChina The Neural Regeneration Co-innovation Center of Jiangsu Province NantongJiangsu ProvinceChina Department of Orthopedics First Affiliated HospitalSchool of MedicineShihezi UniversityShiheziXinjiang Uygur Autonomous RegionChina Department of Orthopedics Cangzhou Central HospitalCangzhouHebei ProvinceChina

The extracellular matrix,which includes collagens,laminin,or fibronectin,plays an important role in peripheral nerve ***,a Schwann cell-derived extracellular matrix with classical biomaterial was used to mimic the neural ***,extensive clinical use of Schwann cells remains limited because of the limited origin,loss of an autologous nerve,and extended in vitro culture *** the present study,human umbilical cord-derived mesenchymal stem cells（h UCMSCs）,which are easily accessible and more proliferative than Schwann cells,were used to prepare an extracellular *** identified the morphology and function of h UCMSCs and investigated their effect on peripheral nerve *** with a non-coated dish tissue culture,the h UCMSC-derived extracellular matrix enhanced Schwann cell proliferation,upregulated gene and protein expression levels of brain-derived neurotrophic factor,glial cell-derived neurotrophic factor,and vascular endothelial growth factor in Schwann cells,and enhanced neurite outgrowth from dorsal root ganglion *** findings suggest that the h UCMSC-derived extracellular matrix promotes peripheral nerve repair and can be used as a basis for the rational design of engineered neural niches.

关键词： umbilical Schwann regeneration scaffold neurotrophic biomaterial niche fibronectin glial engineered

Development and validation of a prognostic immunoinflammatory index for patients with gastric cancer

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World Journal of Gastroenterology 2024年第24期30卷 3059-3075页

作者： zhi-Chang Ba Xi-Qing Zhu zhi-guo Li yuan-Zhou Li Department of Radiology Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina Department of Gastrointestinal Surgery Harbin Medical University Cancer HospitalHarbin 150081Heilongjiang ProvinceChina

BACKGROUND Studies have demonstrated the influence of immunity and inflammation on the development of *** single biomarkers of immunity and inflam-mation have been shown to be clinically predictive,the use of biomarkers integrating both to predict prognosis in patients with gastric cancer remains to be *** To investigate the prognostic and clinical significance of inflammatory biomarkers and lymphocytes in patients undergoing surgical treatment for gastric *** Univariate COX regression analysis was performed to identify potential prognostic factors for patients with gastric cancer undergoing surgical *** absolute shrinkage and selection operator-COX(LASSO-COX)regression analysis was performed to integrate these factors and formulate a new prognostic immunoinflammatory index(PII).The correlation between PII and clinical charac-teristics was statistically *** incorporating the PII score were devised and validated based on the time-dependent area under the curve and decision curve *** Patients exhibiting elevated neutrophil-to-lymphocyte ratio,platelet-to-lymphocyte ratio,and systemic immune inflammatory index displayed inferior progression-free survival(PFS)and overall survival(OS).Conversely,low levels of CD3(+),CD3(+)CD8(+),CD4(+)CD8(+),and CD3(+)CD16(+)CD56(+)T lymphocytes were associated with improved PFS and OS,while high CD19(+)T lymphocyte levels were linked to worse PFS and *** PII score demonstrated associations with tumor characteristics(primary tumor site and tumor size),establishing itself as an independent prognostic factor for both PFS and ***-dependent area under the curve and decision curve analysis affirmed the effectiveness of the PII-based nomogram as a robust prognostic predictive *** PII may be a reliable predictor of prognosis in patients with gastric cancer undergoing surgical treatment,and it offers insights into cancer-related immune-inflammatory re

关键词： Gastric cancer Immunity Inflammation Prognosis Nomogram

Preparation of PVA/GO/h-BN Janus Film with High Thermal Conductivity and Excellent Flexibility via a Density Deposition Self-assembly Method

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Chinese Journal of Polymer Science 2024年第8期42卷 1217-1226页

作者： Fang-Hua Luo zhi-Tao Dong guo-Hua Chen Chen Ma Huai-yuan Wang College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China College of Materials Science and Engineering Huaqiao UniversityXiamen 361000China School of Chemical Engineering and Technology and State Key Laboratory for Chemical Engineering Tianjin UniversityTianjin 300350China

Janus films with asymmetric physical/chemical properties have attracted con siderable attention due to their promising applications in personal thermal management,electronic skin s,sensors,actuators,***,traditional methods for fabricating Janus films conventionally need the assistance of an interface or auxiliary equipment,which are usually complex and ***,flexible poly(vinyl alcohol)(PVA)/graphene oxide(GO)/h-BN(recorded as PVA/GO/h-BN)Janus films with thermally,optically,and electrically anisotropic properties are fabricated by a simple density deposition self-assem bly method,which just utilizes the density difference between GO and h-BN during water *** results show that the two sides of the acquired Janus films have obvious asymmetric *** the original state of the PVA/GO/h-BN Janus films,the thermal conductivity of the GO side(10.06 W·m^(-1)·K^(-1))is generally lower than that of the h-BN side(10.48W·m^(-1)·K^(-1)).But after GO is reduced,the thermal conductivity of the rGO side reaches 12.17 W·m^(-1)·K^(-1),surpassing that of the h-BN *** addition,the relative reflectance of the h-BN side of Janus film is also significantly higher than that of the rGO side,and the su rface resistance difference between the two sides is about 4 orders of *** prepared PVA/GO/h-BN Janus films show great application potential in human thermal management,light conversion switches,and electronic *** study provides a simple and versatile strategy for fabricating Janus films with multifunctional(such as thermal,optical,and electrical)anisotropies.

关键词： Janus films PVA/GO/h-BN Density deposition self-assembly method

Double-confined nanoheterostructure Sb/Sb_(2)S_(3)@Ti_(3)C_(2)T_(x)@C toward ultra-stable Li-/Na-ion batteries

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Rare Metals 2024年第5期43卷 2067-2079页

作者： Dan Wang Qun Ma Huan He zhi-yuan Wang Run-guo Zheng Hong-Yu Sun Yan-guo Liu Chun-Li Liu School of Materials Science and Engineering Northeastern UniversityShenyang110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province Qinhuangdao 066004China Department of Physics and Oxide Research Center Hankuk University of Foreign StudiesYongin 17035Korea

Antimony-based materials with high capacities and moderate potentials are promising anodes for lithium-/-sodium-ion ***,their tremendous volume expansion and inferior conductivity lead to poor structural stability and sluggish reaction ***,a doubleconfined nanoheterostructure Sb/Sb_(2)S_(3)@Ti_(3)C_(2)T_(x)@C has been fabricated through a solvothermal method followed by low-temperature heat *** dual protection of“MXene”and“carbon”can better accommodate the volume expansion of Sb/Sb_(2)S_(3).The strong covalent bond(Ti-S,Ti-O-Sb,C-O-Sb)can firmly integrate Sb-based material with Ti_(3)C_(2)T_(x)and carbon,which significantly improves the structure *** addition,the carbon layer can restrain the oxidation of MXenes,and the nano-Sb/Sb_(2)S_(3)can facilitate electron/ion transport and suppress the restacking of *** heterogeneous interface between Sb and Sb_(2)S_(3)can further promote interfacial charge *** MXene-Sb/Sb_(2)S_(3)@C-1 with the optimal Sb content shows high specific capacities,comparable rate properties and ultra-stable cycling performances(250 m Ah·g^(-1)after 2500 cycles at 1 A·g^(-1)for sodium-ion batteries).Ex situ X-ray diffractometer(XRD)test reveals the storage mechanism including the conversion and alloying process of MXene-Sb/Sb_(2)S_(3)@*** voltammetry(CV)test results demonstrate that the pseudocapacitance behavior is dominant in MXene-Sb/Sb_(2)S_(3)@C-1,especially at large *** design paves the way for exploring high-performance alloy-based/conversion-type anode for energy storage devices.

关键词： Sb/Sb_(2)S_(3) MXene Carbon Anode Lithium-ion batteries Sodium-ion batteries