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大豆脲酶诱导碳酸钙固化黄河泥沙水稳定性试验研究

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水利学报 2024年第1期55卷 71-79页

作者：王钰轲陈浩宋迎宾王振海钟燕辉张蓓郑州大学水利与交通学院河南郑州450001 重大基础设施检测修复技术国家地方联合工程实验室河南郑州450001 地下工程灾变防控省部共建协同创新中心河南郑州450001 黄河水利委员会黄河水利科学研究院河南郑州450003 水利部堤防安全与病害防治工程技术研究中心河南郑州450003

随着国家“交通强国”战略的提出,沿黄工程建设发展迅速,填筑用土需求剧增。黄河泥沙作为填筑材料的可行性已被证实,但其在多雨地区的服役性能需要改善,探索一种生态、高效的泥沙加固方法提高其水稳定性十分关键。本文基于酶诱导碳酸钙... 详细信息

随着国家“交通强国”战略的提出,沿黄工程建设发展迅速,填筑用土需求剧增。黄河泥沙作为填筑材料的可行性已被证实,但其在多雨地区的服役性能需要改善,探索一种生态、高效的泥沙加固方法提高其水稳定性十分关键。本文基于酶诱导碳酸钙沉淀(EICP)技术固化黄河泥沙的方法,分别开展了常规浸水条件和干湿循环条件下固化黄河泥沙的水稳定性试验,研究了浸水后试样的质量损失及强度折损情况,分析了干湿循环对固化后黄河泥沙试样强度软化系数的影响规律。结果表明:采用EICP技术固化的黄河泥沙试样浸水崩解过程相比原状试样更加缓慢;胶结液浓度1.5 mol/L的黄河泥沙试样长期(56 d)浸水后,几乎保持完整,质量损失率仅为6.36%,强度折损率仅为6.21%;10次干湿循环后,不同胶结液浓度处理后的黄河泥沙试样均出现了不同程度的颗粒松散和脱落现象,胶结液浓度1.5 mol/L、灌浆10次的黄河泥沙试样的抗压强度损失仅为9.96%,抗干湿循环能力最强。利用EICP技术可以有效的固化黄河泥沙并提升其水稳定性,这对推进黄河泥沙的资源化利用进程十分重要。

关键词：黄河泥沙 EICP 干湿循环质量损失强度损失软化系数

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长期循环荷载下黄泛区黄河泥沙的变形特性及安定性分析

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铁道科学与工程学报 2024年第5期21卷 1866-1875页

作者：王钰轲蒋睿贾朝军余翔钟燕辉郑州大学水利与交通学院河南郑州450001 中南大学土木工程学院湖南长沙410075 重大基础设施检测修复技术国家地方联合工程实验室河南郑州450001 水利与交通基础设施安全防护河南省协同创新中心河南郑州450001

随着国家“黄河高质量发展”战略的提出,沿黄工程建设飞速发展,填筑土体材料需求量剧增,建筑资源短缺的问题突显。黄河泥沙作为一种新型工程填料,其资源利用前景被相关部门和研究人员重视。为研究长期循环荷载作用下的黄河泥沙的动力服... 详细信息

随着国家“黄河高质量发展”战略的提出,沿黄工程建设飞速发展,填筑土体材料需求量剧增,建筑资源短缺的问题突显。黄河泥沙作为一种新型工程填料,其资源利用前景被相关部门和研究人员重视。为研究长期循环荷载作用下的黄河泥沙的动力服役特性,选取黄河泥沙典型试样,基于GDS三轴试验系统进行了排水条件下的大周次(10000次)循环三轴试验,结合安定理论系统分析围压、循环应力比、加载频率和密实度对黄河泥沙变形特性的影响,并对黄河泥沙的长期动力稳定性进行研究。研究结果表明:累积应变和回弹应变随着围压的增大而增大,随着频率的升高和密实度的增大而减小,循环应力比较小时,应变累积在加载初期几百次循环内就迅速稳定;随着循环应力比增大,应变的发展逐渐具有蠕变的性质,在5000次循环后仍不断累积;随着循环应力比继续增大,轴向应变将在加载初期迅速增大,泥沙试样在很少的周次内达到破坏状态。通过与代表性的相似土体进行对比,发现黄河泥沙的蠕变性介于粉土和砂砾土之间。基于黄河泥沙的安定性分析,提出了黄河泥沙容许循环应力比的表达式,用以初步判断排水状态下黄河泥沙的长期动力稳定状态。研究结果为泥沙土在实际工程中的进一步应用和推广提供了参数支撑。

关键词：黄河泥沙排水条件循环荷载变形特性安定理论

Stability analysis of layered slopes in unsaturated soils

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 378-387页

作者： Guangyu DAI Fei ZHANG yuke wang Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Jiangsu Province's Geotechnical Research Center Nanjing 210098China College of Water Conservancy Engineering Zhengzhou UniversityZhengzhou 450001China

This study presents stability analyses of layered soil slopes in unsaturated conditions and uses a limit equilibrium method to determine the factor of safety involving suction stress of unsaturated ***-dimensional steady infiltration and evaporation conditions are considered in the stability *** example of a two-layered slope in clay and silt is selected to verify the used method by comparing with the results of other *** analyses are conducted to explore the influences of the matric suction on the stability of layered soil *** obtained results show that larger suction stress provided in unsaturated clay dominates the stability of the layered ***,the location and thickness of the clay layer have significant influences on slope *** the water level decreases,the factor of safety reduces and then increases gradually in most ***/evaporation can obviously affect the stability of unsaturated layered slopes,but their influences depend on the soil property and thickness of the lower soil layer.

关键词： slope stability suction stress unsaturated soil layered slope limit equilibrium

PDMS/PVDF静电纺丝膜的制备及油水分离性能研究

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中国塑料 2024年第1期38卷 28-34页

作者：李杰路祎祎石文天郭云杰王宇科北京工商大学机械工程系北京100048

利用静电纺丝技术制备具有特殊浸润性表面用于油水分离研究。对比聚偏氟乙烯(PVDF)与聚二甲基硅氧烷(PDMS)不同配比下静电纺丝的成膜效果,并进行性能表征。研究表明,适量的PVDF可以对PDMS起到助纺与增塑的效果,且微球的存在使膜层表现... 详细信息

利用静电纺丝技术制备具有特殊浸润性表面用于油水分离研究。对比聚偏氟乙烯(PVDF)与聚二甲基硅氧烷(PDMS)不同配比下静电纺丝的成膜效果,并进行性能表征。研究表明,适量的PVDF可以对PDMS起到助纺与增塑的效果,且微球的存在使膜层表现出更好的疏水性。此外,膜层具有的对水高黏附性是受到毛细吸附与静电作用双重影响。当PVDF与PDMS的配比为2∶1时,膜层显示出对油包水乳液良好的选择透过性,水接触角可达150°,油接触角几乎为0°,油水分离率在98%以上,是油水分离材料良好的候选物。

关键词：静电纺丝聚二甲基硅氧烷聚偏氟乙烯油水分离

发芽对不同品种糙米γ-氨基丁酸及酚类物质累积的调控作用

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食品与发酵工业 2024年第15期50卷 272-280页

作者：汪昱柯王冕王晓晴宋世钰谢翀蔡敬敬胡标林杨润强南京农业大学食品科学技术学院全谷物食品工程研究中心江苏南京210095 江苏百斯特鲜食有限公司江苏淮安223200 江西省农业科学院水稻研究所江西南昌330299

发芽可激活种子的内源酶,增加γ-氨基丁酸(γ-aminobutyric acid,GABA)、酚酸等功能成分含量。该研究以粤秀优197、万象优197、泰丰优197等12个糙米品种为研究对象,研究30℃黑暗催芽36 h后GABA与酚类物质合成情况,分别筛选GABA与酚类物... 详细信息

发芽可激活种子的内源酶,增加γ-氨基丁酸(γ-aminobutyric acid,GABA)、酚酸等功能成分含量。该研究以粤秀优197、万象优197、泰丰优197等12个糙米品种为研究对象,研究30℃黑暗催芽36 h后GABA与酚类物质合成情况,分别筛选GABA与酚类物质含量上升的品种,探究其相关酶活力的变化。结果表明,各品种糙米经发芽后GABA和总酚含量变化不同。万象优197、泰丰优197、万象优111、上两优798和莲玉香2号5个品种糙米的总酚含量较对照显著增加25.97%~178.53%,其中上两优798提高幅度最大。对香豆酸和丁香酸是糙米中主要的酚酸类型,分别占糙米总酚酸的12.37%~43.31%和21.80%~62.08%;然而,不同品种的发芽糙米中酚酸的组成及其含量存在差异。萌发提高了糙米中谷氨酸脱羧酶(glutamic acid decarboxylase,GAD)、苯丙氨酸解氨酶(phenylalanine aminolyase,PAL)、肉桂酸-4-羟化酶(cinnamic acid-4-hydroxylase,C4H)、4-香豆酸辅酶A连接酶(4-coumarate coenzyme A ligase,4CL)等活力,从而实现了GABA和酚类化合物的累积。该研究结果为开发富含生物活性物质的发芽糙米提供数据支撑。

关键词：糙米发芽酚类物质 γ-氨基丁酸

New Insights into the Late Triassic Nadigangri Formation of Northern Qiangtang, Tibet, China： Constraints from U-Pb Ages and Hf Isotopes of Detrital and Magmatic Zircons

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1451-1467页

作者： LI Xueren wang Jian CHENG Leli FU Xiugen wang yuke Chinese Academy of Geological Sciences Beijing 100037 China China University of Geosciences (Beijing) Beijing 100083 China Key Laboratory for Sedimentary Basin and Oil and Gas Resources Ministry of Land and Resources Chengdu Sichuan 610081 China Chengdu Center of China Geological Survey Chengdu Sichuan 610081 China Institute of Mud Logging Technology and Engineering Yangtze University Jingzhou Hubei 434023 China

We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5-225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma （Norian-Rhaetian）, including three predominant groups of 220-225 Ma, 210-217 Ma and 201-205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive ~Hf（t） value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1-1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin.

关键词： U-Pb ages Hf isotope Nadigangri Formation Late Triassic Qiangtang

雅砻江流域深切河谷区滑坡类型、成因及分布规律——以子拖西―麻郎错河段为例

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中国地质 2024年第2期51卷 511-524页

作者：冉涛徐如阁周洪福张景华陈浩王羽珂孙洁崔炎宗中国地质调查局成都地质调查中心(西南地质科技创新中心) 四川成都610218 山东科技大学地球科学与工程学院山东青岛266590 华北水利水电大学地球科学与工程学院河南郑州450045

【研究目的】雅砻江流域是中国西部重要的林牧业基地、水电能源基地和少数民族聚居区,开展流域内的滑坡成因和分布规律研究,对于制定科学的防灾减灾策略、保障经济社会稳定发展具有重要意义。【研究方法】以雅砻江中游深切河谷区子拖西... 详细信息

【研究目的】雅砻江流域是中国西部重要的林牧业基地、水电能源基地和少数民族聚居区,开展流域内的滑坡成因和分布规律研究,对于制定科学的防灾减灾策略、保障经济社会稳定发展具有重要意义。【研究方法】以雅砻江中游深切河谷区子拖西―麻郎错河段为研究区,通过高分辨率卫星遥感解译、InSAR分析、结合现场调查获取滑坡基础数据;采用工程地质分析方法总结分析典型的滑坡类型及其成因机制;利用GIS空间分析和统计方法,揭示滑坡的分布规律及发育的优势范围。【研究结果】(1)研究区内共查明滑坡606处,其中面积104~105m^(2)的滑坡数量最多,约占总数的60%;面积103~104m^(2)和面积105~106m^(2)的滑坡数量相当,各约占总数的20%;(2)根据主控诱发因素将滑坡划分为降雨诱发型、构造控制型、开挖诱发型、河流侵蚀型和蓄水诱发型等5种主要类型;降雨和蓄水对岩土体强度的弱化效应、断裂构造对岩体结构及其力学性质的劣化效应、开挖和河流侵蚀对斜坡前缘抗滑支撑作用的解除效应等是导致滑坡形成的关键机理;(3)海拔高程2500~3500 m、坡度15°~35°、坡向NE-E和S-W是滑坡发育的优势地形范围;(4)由薄层状板岩、粉砂质板岩构成的软变质岩组是滑坡发育的优势岩组,花岗岩、石英闪长岩等坚硬侵入岩构成的岩浆岩组中滑坡最不发育;(5)康都断层、千杯尼玛断层、祝桑断层、唐岗断层、霍泽扎日断层和涅达断层这6条断层对滑坡的影响不显著,研究区下游麻子石断层、程章断层、然公断层、鸡打—米龙—木灰断层两侧及其交汇部位滑坡发育最为密集;(6)滑坡发育分布与河流水系距离之间呈明显的负相关性,距河流水系0~0.5 km是滑坡发育的优势距离,宏观上滑坡沿着河谷成带状集中分布。【结论】研究成果可以为认识雅砻江深切河谷区滑坡的成因和规律,防控流域链式灾害风险提供重要的科学依据。

关键词：雅砻江流域滑坡遥感解译合成孔径雷达干涉测量成因机制空间分布地质灾害调查工程

Multi-Functional Supramolecular-Polymeric Hybrid Hydrogel for Promoting Cutaneous Wound Repair

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Chinese Journal of Chemistry 2023年第20期41卷 2657-2663页

作者： Qingcong Wei Liyang Jia yuke wang Weiwei Zhang Zhiguo Hu Qigang wang Qing Wu Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationHenan Engineering Research Centre of Chiral Hydroxyl PharmaceuticalSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People's HospitalSchool of MedicineTongji UniversityShanghai200434 China School of Chemical Science and Engineering Tongji UniversityShanghai200092 China

Supramolecular-polymeric hybrid hydrogels combining advantages of the assembled supramolecular networks and polymeric networks have attracted considerable attention ***,they are rarely used as multi-functional wound dressing *** this work,we report a supramolecular-polymeric hybrid hydrogel consisting of a co-assembled DBS-COOH/Naproxen network(DBS/NAP)and a polymeric gelatin(G)/quaternary ammonium group(Q)and phenylboronic acid groups(PBA)-grafted chitosan(QCS-PBA)network(G/QCS)for accelerating skin wound *** polymeric networks could obviously enhance the mechanical properties of the drug-derived supramolecular networks.Q groups endowed the hydrogel with enhanced antibacterial *** ester crosslinking between PBA groups and diol groups in DBS-COOH could effectively scavenge reactive *** hybrid hydrogel exhibited tunable mechanical and adhesive properties due to the temperature-responsive gelatin *** could gradually release from hybrid hydrogel networks thus continuously relieving ***,the biocompatible,adhesive,antibacterial and antioxidant hybrid G/QCS-DBS/NAP gel could promote the in vivo healing stages in a full-thickness wounds with increased collagen deposition,upregulated CD31 expression and down-regulated TNF-α***,this multi-functional supramolecular-polymeric hybrid hydrogel exhibited great potential for treating skin defects as promising wound dressing materials.

关键词： Self-assembly Hydrogel Chitosan Gelatin Wound healing

A novel model of the carbon cycle in the Cambrian ocean

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Science China Earth Sciences 2024年第6期67卷 1759-1778页

作者： Huajian wang Shuichang ZHANG Xiaomei wang Jin SU Yuntao YE yuke LIU Key Laboratory of Petroleum Geochemistry Research Institute of Petroleum Exploration and DevelopmentChina National Petroleum CorporationBeijing 100083China Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China

The classic model of the carbon cycle suggests that the extensive burial of ^(12)C-enriched organic carbon leads to a positive carbon isotope(δ^(13)C)excursion(CIE),while massive oxidation of organic carbon results in a negative ***,global events such as the BAsal Cambrian Carbon isotope Excursion(BACE)and the Steptoean Positive Carbon Isotope Excursion(SPICE)are global negative and positive δ^(13)C excursions,respectively,and they also exhibit significant organic carbon burial anomalies,displaying decoupling between carbon isotope anomalies and organic carbon *** on the analyses of the Cambrian carbon cycle and paleoceanographic evolution records from well Tadong2 in the Tarim Basin,we propose a novel model of the carbon cycle in the Cambrian ocean that incorporates oceanic dissolved organic carbon(DOC).Our findings are as follows.(1)The Cambrian ocean maintained substantial DOC reservoirs,which were regulated by ocean currents and paleo-redox conditions and exerted significant influence on the oceanic carbon cycle.(2)The oxidation of the oceanic DOC reservoirs during the early Cambrian led to the BACE and the Asian Phenomenon of the Cambrian petroleum systems,while the expansion of the oceanic DOC reservoirs during the SPICE resulted in a global positive δ^(13)C excursion and the absence of significant organic carbon burial.(3)The deep-basin sedimentary environment in the eastern depression of the Tarim Basin may have fostered the development of organic-rich black shales during the Furongian Series,corresponding to organic carbon burial during the SPICE and representing potential prospects for ultra-deep oil and gas *** research should focus on the formation mechanism,reserve scale,and influencing factors of the oceanic DOC reservoirs,as well as their resource and environmental *** is expected that new breakthroughs will be made in the fields of Earth system science and oil and gas exploration.

关键词： Carbon isotope Organic carbon BACE SPICE Dissolved organic carbon Climate change Black shale