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Glycerol solutions of highly concentrated biomineral counter-ions towards water-responsive mineralization: Demonstration on bacterial cellulose and its application in hard tissue repair

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Nano Research 2024年第3期17卷 2154-2163页

作者： Yunfei Zhao Xiaohao Liu Zhi Zhou Chaobo Feng Nan luo Jiajun Yan Shuo Tan Yang Lu Feng Chen Bing-qiang Lu Shisheng He Department of Orthopedic Spinal Pain Research InstituteShanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Preventive Dentistry Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Research Institute of StomatologyShanghai 200011China

Mineralization has found widespread use in the fabrication of composite biomaterials for hard tissue *** current mineralization processes are mainly carried out in neutral aqueous solutions of biomineral counter-ions(a pair of cation and anion that form the corresponding minerals at certain conditions),which are stable only at very low *** typically results in inefficient mineralization and weak control over biomineral ***,we find that,in the organic solvent glycerol,a variety of biomineral counter-ions(e.g.,Ca/PO_(4),Ca/CO_(3),Ca/SO_(4),Mg/PO_(4),or Fe/OH)corresponding to distinct biominerals at significantly high concentrations(up to hundreds-fold greater than those of simulated body fluid(SBF))are able to form translucent and stable solutions(mineralizing solution of highly concentrated counter-ions(MSCIs)),and mineralization can be triggered upon them with external solvents(e.g.,water or ethanol).Furthermore,with pristine bacterial cellulose(BC)membrane as a model,we demonstrate an effective and controllable mineralization performance of MSCIs on organic *** approach not only forms the homogeneous biominerals on the BC fibers and in the interspaces,but also provides regulations over mineralization rate,mineral content,phase,and *** resulting mineralized BC membranes(MBCs)exhibit high cytocompatibility and favor the proliferation of rat bone marrow mesenchymal stem cells(rBMSC).Following this,we prepare a mineralized bone suture(MBS)from MBC for non-weight bearing bone fixation,which then is tested on a rabbit median sternotomy *** shows firm fixation of the rabbit sternum without causing discernible toxicity or inflammatory *** study,by extending the mineralization to the organic solution system of highly concentrated counter-ions,develops a promising strategy to design and build targeted mineral-based composites.

关键词： biomineralization organic solvent bacterial cellulose(BC) hard tissue repair

风险视域下的超大城市社区韧性:结构、梗阻与进路——基于W市新冠肺炎疫情社区治理的多案例分析

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城市问题 2022年第5期 86-94页

作者：罗强强陈涛明承瀚华中科技大学公共管理学院城市管理系湖南农业大学公共管理与法学学院

基于W市16个社区新冠肺炎疫情治理的田野调查,运用扎根理论构建社区韧性结构体系及其关系模型。研究发现,社区韧性由组织韧性、设施韧性、制度韧性、居民韧性、技术韧性五个维度构成,表征了克服风险情境中超大城市治理负荷的应然能力。... 详细信息

基于W市16个社区新冠肺炎疫情治理的田野调查,运用扎根理论构建社区韧性结构体系及其关系模型。研究发现,社区韧性由组织韧性、设施韧性、制度韧性、居民韧性、技术韧性五个维度构成,表征了克服风险情境中超大城市治理负荷的应然能力。然而,实践中超大城市社区应急治理往往面临社区自治体系超载、应急基础设施薄弱、应急制度运转欠佳、集体行动力发散、数字技术治理悬浮等现实梗阻。完善社区应急组织的整合性、强化社区应急设施的平衡性、增强社区应急制度的协调性、激发社区居民应急的行动力、提升社区应急技术的智治性,是构建社区韧性体系,保障超大城市善治的实践进路。

关键词：超大城市社区韧性应急治理新冠肺炎疫情案例研究

Viscosity profile prediction of a heavy crude oil during lifting in two deep artesian wells

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Chinese Journal of Chemical Engineering 2017年第7期25卷 976-982页

作者： Yibo Li Hao Gao Wanfen Pu Bing Wei Yafei Chen Dong Li qiang luo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Experiment and Detection Xinjiang Oilfield CompanyPetroChina

It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. The impacts of well conditions including temperature, pressure and shear rate, on the crude oil rheology were comprehensively investigated and correlated using several empirical rheological models. The experimental data indicate that this heavy oil is very sensitive to temperature as result of microstructure change caused by hydrogen bonding. The rheological behavior of the heavy oil is also significantly impacted by the imposed pressure, i.e., the viscosity flow activation energy(Eμ) gently increases with the increasing pressure. The viscosity–shear rate data are well fitted to the power law model at low temperature. However, due to the transition of fluid feature at high temperature(Newtonian fluid), the measured viscosity was found to slightly deviate from the fitting data. Combining the evaluated correlations, the viscosity profile of the heavy crude oil in these two deep artesian wells as a function of well depth was predicted using the oilfield producing data.

关键词：油粘度预测承压剖面举升微观结构变化流变性质剪切速率

The Residual Strain Measurement of Thin Conductive Metal Wire after Electrical Failure with SEM Moir

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Acta Mechanica Solida Sinica 2016年第4期29卷 371-378页

作者： Yanjie Li Huimin Xie Qinghua Wang Mengmeng Zhou Manqiong Xu qiang luo Changzhi Gu AML Department of Engineering Mechanics Tsinghua University School of Civil Engineering and Architecture University of Jinan National Institute of Advanced Industrial Science and Technology Institute of Physics Chinese Academy of Sciences

In this study, the residual strain of a thin conductive metal wire on a polymer substrate after electrical failure is measured with SEM moir′e. Focused ion beam(FIB) milling is applied to fabricate micron moir′e gratings on the surfaces of constantan wires and the random phase shifting technique is used to process moir′e fringes. The virtual strain method is briefly introduced and used to calculate the real strain of specimens. In order to study the influence of a defect on the electrical failure of the constantan wire, experiments were conducted on two specimens, one with a crack, while the other one without any crack. By comparing the results, we found that the defect makes the critical beam current of electrical failure decrease. In addition, the specimens were subjected to compression after electrical failure, in agreement with the observed crack closure of the specimen. The successful results demonstrate that the moir′e method is effective to characterize the full-field deformation of constantan wires on the polymer membrane, and has a good potential for further application to the deformation measurement of thin films.

关键词： SEM moir′e residual strain metal wire focused ion beam(FIB)

Publication trends in studies examining radix notoginseng as a treatment for ischemic brain injury

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Neural Regeneration Research 2014年第17期9卷 1635-1642页

作者： Haiping Li luo qiang Chunyang Zhang Chaohui Wang Zhenxing Mu Ligang Jiang Department of Neurology Affiliated Hospital of Beihua University

Acute ischemic stroke has become a major disease burden with high mortality and morbidity rates. There is a lack of evidence-based medicine confirming the efficacy of common treatments. Panax notoginseng saponins, the main active ingredient of radix notoginseng, have a neuro- protective role in ischemic brain injury, and have been popularized as a maintenance treatment for acute cerebral infarction and its sequelae. We conducted literature searches on the Web of Science, ***, Cochrane Collaboration, CNKI, Wanfang and the China Scientific ＆ Technological Achievements Database and analyzed the experimental and clinical outcomes of studies investigating the use of radix notoginseng in the treatment of ischemic brain injury to improve the understanding of relevant research trends and existing problems. We found that over the past 10 years, China has maintained its interest in Panax notoginseng research, while such studies are scarce on the Web of Science. However, Chinese researchers often focus on the neuroprotective role of radix notoginseng in ischemic brain injury, but there are no large-scale clinical data to confirm its efficacy and safety. There remains a need for more rigorous large-sample randomized controlled clinical trials with long-term follow-up, to determine whether radix notoginseng lowers stroke recurrence and improves patient＇s quality of life.

关键词： nerve regeneration neuroprotection Panax notoginseng cerebral ischemia stroke Panax notoginseng saponins basic clinical neural regeneration

Adaptive strategies of high and low nucleic acid prokaryotes in response to declining resource availability and selective grazing by protozoa

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Science China Earth Sciences 2024年第6期67卷 1872-1884页

作者： Chen HU Liuqian YU Xiaowei CHEN Jihua LIU Yao ZHANG John BATT Xilin XIAO qiang SHI Rui ZHANG Tingwei luo Nianzhi JIAO Dapeng XU College of the Environment and Ecology Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesFujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Joint Lab for Ocean Research and Education(LORE)of Dalhousie University Canadaand Shandong University and Xiamen UniversityXiamen 361102China Earth Ocean and Atmospheric Sciences ThrustThe Hong Kong University of Science and Technology(Guangzhou)Guangzhou 510000China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada Institute for Advanced Study Shenzhen UniversityShenzhen 518060China Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361102China

Prokaryotes play a fundamental role in global ocean biogeochemical ***,how the abundance and metabolic activity of ecologically distinct subgroups(i.e.,high nucleic acid(HNA)and low nucleic acid(LNA)cells),and their regulating factors,change in response to changing marine environmental conditions remains poorly ***,we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume(117,000 L)macrocosm that facilitates community-level *** found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce,leading to a steadily increasing contribution of LNA cells to prokaryotic ***,as resources in the macrocosm became limited,protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm *** findings highlight the resilience of LNA cells in resource-limited environments,illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions,and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts.

关键词： Microbial loop Macrocosm experiment Prokaryote Top-down and bottom-up controls Carbon flow

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Evolution and function of residual solvent in polymer-Li2B12H12 composite solid electrolyte

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Rare Metals 2024年第8期43卷 3748-3757页

作者： Xiang-Yang Ye Ke-Pan Bao Sai-Nan luo Xin Li Tai-qiang Chen Shui-Xin Xia Tao Yuan Yue-Peng Pang Shi-You Zheng School of Materials and Chemistry University of Shanghai for Science and Technology Department of Materials Science and Engineering National University of Singapore

Composite solid electrolytes（CSEs） containing polymer matrices and inorganic fillers hold promise for the next generation of solid-state ***,the role of residual solvents in CSEs remains *** study investigated the evolution and function of the residual solvent in a polymer-Li2B12H12CSE.A partial reaction occurred between Li2B12H12and solvent N,N-dimethylformamide（DMF）,which produced dimethylaminomethanol（DMAM） in the *** functional theory calculations have revealed that DMA M forms stronger hydrogen bonds with polyvinylidene fluoride chains than DMF,which can have a plasticizing effect on the polymer matrix,leading to lower crystallinity and quicker segment ***,this CSE exhibited improved Li-ion conducting properties,enabling the stable cycling of Li‖LiFePO4solid-state *** study provided insights into the role of residual solvents in CSEs.

关键词： Composite solid electrolyte Residual solvent Lithium borohydride Plasticizing effect

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-Hao Zeng Shi-Dan Zhu Ying-Hua luo Wei Shi Yong-qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Synthesis and Compressive Response of Microcellular Foams Fabricated from Thermally Expandable Microspheres

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Chinese Journal of Polymer Science 2019年第3期37卷 279-288页

作者： Rui-Zhi Zhang Ju Chen Mao-Wei Huang Jian Zhang Guo-qiang luo Bao-Zhen Wang Mei-Juan Li qiang Shen Lian-Meng Zhang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology School of Civil and Hydraulic Engineering Hefei University of Technology School of Chemistry Chemical Engineering and Life Sciences Wuhan University of Technology

Cellular foams are widely applied as protective and energy absorption materials in both civil and military fields. A facile and simple one-step heating method to fabricate polymeric foams is measured by adopting thermally expandable microspheres(TEMs). The ideal foaming parameters for various density foams were determined. Moreover, a mechanical testing machine and split Hopkinson bar(SHPB) were utilized to explore the quasi-static and dynamic compressive properties. Results showed that the cell sizes of the as-prepared TEMs foams were in the micrometer range of 11 μm to 20 μm with a uniform cell size distribution. All the foams exhibited good compressive behavior under both quasi-static and high strain rate conditions, and were related to both foam densities and strain rates. The compressive strength of the TEMs foams at 8400s^(-1) was up to 4 times higher than that at 10^(-4)s^(-1). The effects exerted by the strain rate and sample density were evaluated by a power law equation. With increasing density, the strain rate effect was more prominent. At quasistatic strain rates below 3000s^(-1) regime, initial cell wall buckling and subsequent cellular structure flattening were the main failure mechanisms. However, in the high strain rate(HSR) regime(above 5000s^(-1)), the foams were split into pieces by the following transverse inertia force.

关键词： Thermally expandable microspheres Compressive response Split Hopkinson bar(SHPB) Microcellular Failure mechanism