检索结果-南通市图书馆

Preparation of Hollow-Porous Rosin-Based Polyurethane Microspheres with pH-Responsive Characteristics

在线全文

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2022年第4期10卷 1049-1061页

作者： Caili Yu hao Liu Jintao shao Faai Zhang College of Chemistry and Biology Engineering Guilin University of TechnologyGuilin541004China

Preparation of polymer microspheres from naturally occurring resource is a ***,a rosin-based polyol(RAG)was used to prepare polyurethane resin(RPU)firstly,and then act as both self-assembled precursor and emulsifier,rosin based polyurethane microspheres(RPUMs)were *** the process of self-emulsification,the RPU formed vesicles by *** outer shell of the vesicle consisted of hydrophilic segments,while the inner shell contained the hydrophobic *** cross-linking the RPU and removal of the solvent in the core,the porous-hollow microspheres with pH-sensitive were *** microspheres were characterized by optical microscope(OM),scanning electron microscopy(SEM)and transmission electron microscope(TEM).The effect of type and amount of the hydrophilic chain extender,and solvent on the morphology,particle size and distribution,and buffer volume of the microspheres were *** best conditions for synthetic RPUMs were as follows:n_(NCO)/n_(OH)=1,n_(RAG):n_(1-(2-hydroxyethyl)piperazine)=4:6,with azodiisobutyronitrile level of 1.0 wt.%,based on reactive monomers,mixing speed of both emulsification and polymerization at 400 r·min-1,the RPUMs synthesized had porous-hollow structure with a buffer volume of 1.6 mL.

关键词： Polyurethane microspheres rosin-based pH-responsive hollow-porous

Slip Rate of Yema River–Daxue Mountain Fault since the Late Pleistocene and Its Implications on the Deformation of the Northeastern Margin of the Tibetan Plateau

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2015年第2期89卷 561-574页

作者： LUO hao HE Wengui YUAN Daoyang shao Yanxiu Key Laboratory of Active Tectonics and Volcano Institute of GeologyChina Earthquake Administration Lanzhou Institute of Seismology China Earthquake Administration Lanzhou National Geophysical Observatory

The slip rate of Yema River-Daxue Mountain fault in the western segment of Qilian Mountains was determined by the dated offset of river risers or gullies. Results indicate that the left-lateral fault slip rate is 2.82± 0.20 mm/a at Dazangdele site, 2.00 ± 0.24 mm/a at Shibandun site, and 0.50± 0.36 and 2.80±0.33 mm/a at two sites in Zhazihu. The ideal average slip rate of the whole fault is 2.81 ± 0.32 mm/a. The lower slip rate confirms part of the displacement of Altyn Tagh fault was transformed into an uplifting of the strap mountains in the western segment of Qilian Mountains, whereas another part transformed into sinistral displacement of Haiyuan fault. This study illustrates that the slip of large strike-slip faults in the northeastern margin of the plateau transforms into crust thickening at the tip of the fault without large-scale propagation to the outer parts of the plateau.

关键词： Slip rate strike-slip fault Yema River-Daxue Mountain fault Altyn Tagh fault,Qilian ranges

Influence of rare earth element terbium doping on microstructure and magnetostrictive properties of Fe_(81)Al_(19) alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2022年第3期40卷 451-456,I0004页

作者： rui Wang Xiao Tian Zhanquan Yao Xuan Zhao Hongbo hao Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials School of Physics and Electronic InformationInner Mongolia Normal UniversityHohhot 010022China School of Water Conservancy and Civil Engineering Inner Mongolia Agricultural UniversityHohhot 010018China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

Fe_(81)Al_(19)Tb_(x)(x=0,0.05,0.1,0.2,0.3,0.4)alloys were prepared by a non-consumable vacuum arc melting technique under an inert argon gas *** microstructures of the alloys were studied by X-ray diffraction(XRD)and scanning electron microscopy combined with an energy dispersive spectroscopy(SEM/EDS).The magnetic properties and magnetostriction coefficients of the alloys were measured by a vibrating sample magnetometer(VSM)and adifferential resistive strain sensor,*** results show that the Fe_(81)Al_(19)alloy consists of a single A2 phase with bcc structure,whereas the Tb doped Fe_(81)Al_(19)alloys are composed of the A2 phase and a small amount of rare earth-rich *** doping of the rare earth element Tb makes the Fe_(81)Al_(19)alloy preferentially oriented along with thecrystal *** the increase of Tb content,the magnetostriction coefficient of the alloy first increases and then *** x=0.1,the magnetostriction coefficient reaches the maximum,which is 146×10^(−6).Compared with the as-cast Fe_(81)Al_(19)alloy(27×10^(−6)),it increases by 441%.The enhanced magnetostrictive properties are mainly attributed to the preferred orientation alongof A2 phase of the Tb doped Fe_(81)Al_(19)alloys and lattice distortion caused by the small amount of rare earth atoms entering the Fe-Al alloy lattice.

关键词： Fe-Al alloy Magnetostriction Lattice distortion Preferred orientation Rare earths

Applicability of Artificial Recharge of Groundwater in the Yongding River Alluvial Fan in Beijing through Numerical Simulation

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2014年第3期25卷 575-586页

作者： Qichen hao Jingli shao Yali Cui Zhenhua Xie School of Water Resources and Environment China University of Geosciences Beijing Institute of Hydrogeology and Engineering Geology

A groundwater transient flow model was developed to evaluate the applicability and effectiveness of artificial recharge scenarios in the middle-upper part of the Yongding River alluvial fan in Beijing. These scenarios were designed by taking into account different types of recharge facilities and their infiltration rate with the Middle Route Project for South-to-North Water Transfer（MRP） as the recharge water source. The simulation results suggest that：（1） the maximum amount of artificial recharge water, for scenario I, would be 127.42×106 m3 with surface infiltration facilities; and would be243.48×106 m3 for scenario II with surface infiltration and recharge wells under the constraint of the upper limit of groundwater;（2） with preferred pattern of recharge facilities, groundwater levels in both optimized recharge scenarios would not exceed the upper limit within the given recharge period; and（3implementation of the recharge scenarios would efficiently increase the aquifer replenishment and the groundwater budget will change from-54.11×106 to 70.89×104 and 183.36×104 m3, respectively. In addition, under these two scenarios groundwater level would rise up to 30 and 34 m, respectively, without increasing the amount of evaporation. The simulation results indicate that the proposed recharge scenarios are practically feasible, and artificial recharge can also contribute to an efficient recovery of groundwater storage in Beijing.

关键词： groundwater modeling artificial recharge infiltration rate groundwater management.

Aggregation and stability of selenium nanoparticles: Complex roles of surface coating, electrolytes and natural organic matter

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第8期130卷 14-23页

作者： Sujuan Yu hao Liu rui Yang Wenjing Zhou Jingfu Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China

The application of selenium nanoparticles(SeNPs)as nanofertilizers may lead to the release of SeNPs into aquatic ***,the environmental behavior of SeNPs is rarely *** this study,using alginate-coated SeNPs(Alg-SeNPs)and polyvinyl alcohol-coated SeNPs(PVA-SeNPs)as models,we systematically investigated the aggregation and stability of SeNPs under various water ***-SeNPs were highly stable in mono-and polyvalent electrolytes,probably due to the strong steric hindrance of the capping ***-SeNPs only suffered from a limited increase in size,even at 2500 mmol/L NaCl and 200 mmol/L MgCl_(2),while they underwent apparent aggregation in CaCl_(2) and LaCl_(3) *** binding of Ca^(2+) and La^(3+) with the guluronic acid part in alginate induced the formation of cross-linking *** organic matter enhanced the stability of Alg-SeNPs in monovalent electrolytes,while accelerated the attachment of Alg-SeNPs in polyvalent electrolytes,due to the cation bridge *** long-term stability of SeNPs in natural water showed that the aggregation sizes of Alg-SeNPs and PVA-SeNPs increased to several hundreds of nanometers or above 10μm after 30 days,implying that SeNPs may be suspended in the water column or further settle down,depending on the surrounding water *** study may contribute to the deep insight into the fate and mobility of SeNPs in the aquatic *** varying fate of SeNPs in different natural waters also suggests that the risks of SeNPs to organisms living in diverse depths in the aquatic compartment should be concerned.

关键词： Selenium nanoparticles Aggregation Stability Surface coating Electrolytes Natural organic matter

Silver vanadate(Ag_(0.33)V_(2)O_(5))nanorods from Ag intercalated vanadium pentoxide for superior cathode of aqueous zinc-ion batteries

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第8期41卷 2844-2852页

作者： Zhi-hao Su Run-hao Wang Jiong-hao Huang rui Sun Zhao-Xia Qin Yu-Fei Zhang hao-Sen Fan School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China

Silver vanadate(Ag_(0.33)V_(2)O_(5))nanorods were successfully synthesized by the pre-intercalation of Ag+into the interlayer of V_(2)O_(5)through a sol-gel method,which presented a favorable electrochemical performance of high capacity,rate capacity,and cycle *** ally,Ag_(0.33)V_(2)O_(5)electrode presented a high capacity of about 311 mAh·g^(-1)at the current density of0.1 A·g^(-1).It also delivered long-term cycling stability(144 mAh·g^(-1)after 500 cycles at 2 A·g^(-1)).The reasons for the superior electrochemical performance were the preintercalation Ag^+extended interlayer distance,and the introduction of elemental silver improved conductivity during charge/***,the Zn^(2+)storage mechanism was revealed by various characteristic *** prepared Ag_(0.33)V_(2)O_(5)nanorods from the sol-gel method were demonstrated as a promising cathode material for aqueous Zn^(2+)batteries.

关键词： Ag_(0.33)V_(2)O_(5)nanorods Aqueous zinc-ion battery Pre-intercalation Electron and ion transport

Oral delivery of ferroptosis inducers for effective treatment of hepatic fibrosis

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7621-7630页

作者： Yinglan Yu Shunlong Zhang Yongfeng Xu hao shao Lei Luo College of Pharmaceutical Sciences Southwest UniversityChongqing 400715China

Liver fibrosis is characterized by the excessive accumulation of extracellular matrix(ECM),which is primarily produced by activated hepatic stellate cells(HSCs).However,effective therapies for hepatic fibrosis are currently *** is a promising anti-fibrotic drug candidate,but its clinical application is hindered by limited ***,we present a novel oral delivery platform that enhances the HSCs uptake of artesunate and induces potent *** platform is vitamin Adecorated nanoparticles encapsulated with *** multifunctional ligand vitamin A interacts with retinol-binding proteins that are highly expressed on the intestinal epithelium to promote transcytosis,highly expressed on the surface of HSCs but lowly expressed in normal *** oral administration,this oral delivery platform enhances transepithelial transport in the intestine,improves drug accumulation in the liver,and continuously increases HSCs uptake of *** drug release in HSCs,artesunate depletes glutathione peroxidase 4 and glutathione,effectively initiating *** vivo experiments demonstrate that this strategy induces pronounced ferroptosis,efficiently relieving liver *** work provides a proof-ofconcept demonstration that an oral delivery strategy for ferroptosis inducers may be beneficial for liver fibrosis treatment.

关键词： liver fibrosis hepatic stellate cells oral delivery intestinal epithelium ferroptosis

Research on active disturbance rejection control method for turbine blade tip clearance

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2019年第10期62卷 1795-1804页

作者： WANG WeiMin shao Xing LI QiHang Gao JinJi hao Zerui Beijing Key Laboratory of Health Monitoring and Self-Recovery for High-End Mechanical Equipment Beijing University of ChemicalTechnologyBeijing100029China Department of Mechanical Engineering Tsinghua UniversityBeijing100084China

Blade tip clearance(BTC) is one of the key factors affecting the efficiency and reliability of high performance turbomachinery such as heavy duty steam turbines, aircraft engines and other gas turbo machines. The self-adjusting ability of BTC according to the operation condition changing is important to meet the requirement of performance. In this paper, the principle and method of adjusting the BTC by controlling the axial displacement of the rotor were proposed and studied. The basic principle is that the BTC of the turbomachinery with a conical tail shroud will be affected by the axial displacement of rotor and thereby can be adjusted by controlling the axial position of rotor, which can be adjusted by the controllable oil pressure acting on the thrust bearing. To reach a higher control precision, lower noise and model perturbation, an adaptive quasi-sliding mode control(AQSMC) algorithm based on the disturbance observer(DOB) was designed, and numerical and experimental investigations were carried out. The numerical simulation results show that this algorithm can not only effectively suppress the disturbance, but also, compared with the general reaching law, effectively reduce the chattering and transient high gain switching effect of the closed-loop controller system and avoid the instability caused by the controller. Based on the DOB-AQSMC algorithm, the BTC was stabilized within 2 s with no overshoot and no misalignment in the test rig, and this algorithm achieves a better control performance than the proportion-integral-differential(PID) algorithm. These achievements can be used to push forward the intelligent turbomachinery development.

关键词： blade tip clearance turbomachinery active disturbance rejection control DOB-AQSM method

Agronomic performances of biodegradable and non-biodegradable plastic film mulching on a maize cropping system in the semi-arid Loess Plateau,China

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2024年第1期34卷 88-96页

作者： hao ZHANG Mengqiong CHEN ruiquan QIAO Fan DING hao FENG rui JIANG Research Center for Cultural Landscape Protection and Ecological Restoration China-Portugal Belt and Road Cooperation Laboratory of Cultural Heritage Conservation ScienceGold Mantis School of ArchitectureSoochow UniversitySuzhou 215006China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China College of Land and Environment Shenyang Agricultural UniversityShenyang 110866China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China

Biodegradable plastic film mulch (PFM) is considered an alternative to non-biodegradable PFM to mitigate the negative impacts of residual ***,the agronomic performance of biodegradable PFM in comparison to non-biodegradable PFM still needs to be *** this study,we evaluated the effects of biodegradable and non-biodegradable PFM on soil physicochemical properties,microbial community,and enzyme activities,as well as maize growth *** and non-biodegradable PFM both increased soil temperature,water content,N content,and microbial biomass and maize yield by up to 30%,but decreased soil enzyme activities as compared to no mulching (control,CK).Most soil physicochemical properties,microbial community,and enzyme activities were similar under non-biodegradable and biodegradable PFM at the early stages of maize ***,at the late stages,soil temperature,water content,mineral N,NO_(3)^(-)-N,ammonia monooxygenase (AMO) activity,and total phospholipid fatty acids (PLFAs) decreased under biodegradable PFM owing to film *** PFM increased soil temperature,water content,and total PLFAs at the early stages of maize growth but decreased soil mineral N and total PLFAs at the late stages,as compared to black *** soil temperature and N availability were the major factors affecting soil microbial community,microbial activity decreased after the fragmentation of biodegradable PFM,owing to the decreased soil temperature,water content,and mineral ***,biodegradable PFM could decrease NO_(3)^(-)-N accumulation in topsoil by decreasing N transformation due to the lower microbial and N-related enzyme (e.g.,AMO) activities,compared with non-biodegradable PFM,which may avoid negative environmental impacts,such as NO_(3)^(-)-N leaching or gas emission after *** yield,height,aboveground biomass,and N uptake under biodegradable PFM were similar to those under non-biodegradable PFM during maize growth,implying that biodegrad

关键词： black plastic film mulching enzyme activity film fragmentation microbial community phospholipid fatty acid white plastic film mulching