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国外畜牧学（猪与禽） 2024年第1期44卷 12-13页

作者： Katia Pedrosa Kathrin Buehler jan Dirk Van der Klis 张相鑫(译) 王晶晶(校) 孟祥光(制图) 不详

维生素D是一种重要的营养物质,母猪在妊娠后期和哺乳期对其需要量非常高。本文概述了维生素D对母猪分娩的影响,提出可以在常规添加维生素D之外补充1,25-二羟基维生素D3糖苷,以缩短分娩时间,减少分娩过程中的人为干预,减少死胎数。

关键词：维生素D 1 25-二羟基维生素D3糖苷分娩

Influence of recycled carbon fiber addition on the microstructure and creep response of extruded AZ91 magnesium alloy

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镁合金学报(英文) 2023年第7期11卷 2518-2529页

作者： Sinan Kandemir jan Bohlen Hajo Dieringa Department of Mechanical Engineering Izmir Institute of TechnologyGülbahçeUrlaIzmir 35430Türkiye Helmholtz-Zentrum Hereon Institute of Material and Process DesignMax-Planck-Straße 1Geesthacht 21502Germany

In this study,the recycled short carbon fiber(CF)-reinforced magnesium matrix composites were fabricated using a combination of stir casting and hot *** objective was to investigate the impact of CF content(2.5 and 5.0 wt.%)and fiber length(100 and 500μm)on the microstructure,mechanical properties,and creep behavior of AZ91 alloy *** microstructural analysis revealed that the CFs aligned in the extrusion direction resulted in grain and intermetallic refinement within the *** comparison to the unreinforced AZ91 alloy,the composites with 2.5 wt.%CF exhibited an increase in hardness by 16-20%and yield strength by 5-15%,depending on the fiber length,while experiencing a reduction in *** the reinforcement content was increased from 2.5 to 5.0 wt.%,strength values exhibited fluctuations and decline,accompanied by decreased *** divergent outcomes were discussed in relation to fiber length,clustering tendency due to higher reinforcement content,and the presence of interfacial products with micro-cracks at the CF-matrix *** creep tests indicated that CFs did not enhance the creep resistance of extruded AZ91 alloy,suggesting that grain boundary sliding is likely the dominant deformation mechanism during creep.

关键词： Metal matrix composites Magnesium alloys Recycled carbon fiber Extrusion,Microstructure Mechanical properties Creep

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硬脂醇甘草亭酸酯绿色合成工艺

化学研究与应用 2024年第3期36卷 681-688页

作者：汪洋程建明阚建伟季浩南京中医药大学药学院江苏南京210023 江苏省天晟药业股份有限公司江苏镇江212415

探索硬脂醇甘草亭酸酯的较优合成条件,为甘草资源的合理开发利用提供依据。采用高效液相色谱法(HPLC)检测硬脂醇甘草亭酸酯的纯度,以硬脂醇甘草亭酸酯的纯度和产率为指标,在单因素实验的基础上,设计正交试验对硬脂醇甘草亭酸酯合成工艺... 详细信息

探索硬脂醇甘草亭酸酯的较优合成条件,为甘草资源的合理开发利用提供依据。采用高效液相色谱法(HPLC)检测硬脂醇甘草亭酸酯的纯度,以硬脂醇甘草亭酸酯的纯度和产率为指标,在单因素实验的基础上,设计正交试验对硬脂醇甘草亭酸酯合成工艺进行优化。本实验得出硬脂醇甘草亭酸酯的最佳合成工艺参数为:以无水碳酸钾作为催化剂,甘草次酸、1-溴十八烷和无水碳酸钾的投料摩尔比为1:1.5:2、反应时间为3h、反应温度为70℃;在此条件下,所得硬脂醇甘草亭酸酯的纯度为98.52%,产率为87%,样品结构经IR、MS、^(1)H NMR确证,质量符合现有硬脂醇甘草亭酸酯质量标准。本实验所得硬脂醇甘草亭酸酯合成工艺具有操作步骤少、三废排放量少、能源消耗少等特点,具有绿色环保的优势,合成的目标产物硬脂醇甘草亭酸酯有望成为中草药化妆品配伍组分的重要来源。

关键词：硬脂醇甘草亭酸酯合成单因素实验正交试验

Reliability Investigation of BiCGStab and IDR Solvers for the Advection-Diffusion-Reaction Equation

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Communications in Computational Physics 2022年第6期32卷 156-188页

作者： Chris Schoutrop jan ten Thije Boonkkamp jan van Dijk Department of Applied Physics Eindhoven University of TechnologyThe Netherlands Department of Mathematics and Computer Science Eindhoven University of TechnologyThe Netherlands

The reliability of BiCGStab and IDR solvers for the exponential scheme discretization of the advection-diffusion-reaction equation is *** resulting discretization matrices have real *** consider BiCGStab,IDR(S),BiCGStab(L)and various modifications of BiCGStab,where S denotes the dimension of the shadow space and L the degree of the polynomial used in the polynomial *** implementations of BiCGStab exist which are equivalent in exact arithmetic,however,not in finite precision *** modifications of BiCGStab we consider are;choosing a random shadow vector,a reliable updating scheme,and storing the best intermediate *** is shown that the Local Minimal Residual algorithm,a method similar to the“minimize residual”step of BiCGStab,can be interpreted in terms of a time-dependent advection-diffusion-reaction equation with homogeneous Dirichlet boundary conditions for the residual,which plays a key role in the convergence *** to the real eigenvalues,the benefit of BiCGStab(L)compared to BiCGStab is shown to be modest in numerical ***-sparse(*** random)shadow residual turns out to be essential for the reliability of *** reliable updating scheme ensures the required tolerance is truly *** the best intermediate solution has no significant *** is to modify BiCGStab with a random shadow residual and the reliable updating scheme,especially in the regime of large P´eclet and small Damk¨ohler *** alternative option is IDR(S),which outperforms BiCGStab for problems with strong advection in terms of the number of matrix-vector *** MATLAB code used in the numerical experiments is available on GitLab:https://***/ChrisSchoutrop/krylov-adr,a C++implementation of IDR(S)is available in the Eigen linear algebra library:http://***.

关键词： BiCGStab IDR shadow residual advection-diffusion-reaction equation

Impact of agricultural landscape structure on the patterns of bird species diversity at a regional scale

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Avian Research 2023年第4期14卷 600-610页

作者： Denisa Dvorakova jan Sipos Josef Suchomel Department of Zoology FisheriesHydrobiology and ApicultureMendel University in BrnoZemedelska 161300BrnoCzech Republic

The loss of bird species diversity is a crucial problem in the European agricultural *** in the area coverage of major land cover types has been mentioned as one of the main factors responsible for bird biodiversity *** this study,we focused on the impact of landscape matrix characteristics on bird species richness and on Faith’s phylogenetic diversity index on a spatial scale of 1000-m radius around the measured occurrence *** investigated how land cover composition affects bird diversity on the landscape scale using nationwide citizen science *** total,168,739 records of bird occurrence in the South Moravian Region of the Czech Republic during growing season from 2009 to 2019 were *** found that the presence of water bodies and wetlands significantly corresponded to the areas of highest bird species *** also revealed that the presence of forests(~60%of the forest in the Czech Republic is occupied by commercial forests),urban areas and arable land were negatively associated with bird species richness and phylogenetic ***(both coniferous and deciduous)and urban habitats were found to have a tendency to host a clustered phylogenetic community structure in comparison with wetland and arable land.A strong negative association between forest proportion and bird diversity led us to conclude that the expansion of the forest(with simple species composition,horizontal and vertical structure)could be one of the critical drivers of the decline of bird species diversity in the European agricultural *** the other hand,our results also pointed out that small woody features(i.e.,woodlots)and scattered woodland shrub vegetation were one of the main landscape characteristics supporting a bird diversity in rural *** is in concordance with other studies which mention these landscape structures as important elements for nesting and foraging of farmland *** thus recommend to maintain and restor

关键词： Bird occurrence Citizen science Conservation Landscape influence Phylogenetic diversity Spatial heterogeneity

Higher-order exceptional points in waveguidecoupled microcavities:perturbation induced frequency splitting and mode patterns

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Photonics Research 2023年第10期11卷 I0011-I0021页

作者： JULIUS KULLIG DANIEL GROM SEBASTIAN KLEMBT jan WIERSIG Institut für Physik Otto-von-Guericke-Universität Magdeburg39106 MagdeburgGermany Technische Physik and Würzburg-Dresden Cluster of Excellence ct.qmat Physikalisches Institut and Wilhelm-Conrad-Röntgen-Research Center for Complex Material SystemsAm HublandUniversity of Würzburg97070 WürzburgGermany

Exceptional points are degeneracies in the spectrum of non-Hermitian open systems where at least two eigenfrequencies and simultaneously the corresponding eigenstates of the Hamiltonian ***,the robust construction of higher-order exceptional points with more than two degenerate eigenfrequencies and eigenstates is challenging but yet worthwhile for *** this paper,we reconsider the formation of higher-order exceptional points through waveguide-coupled microring cavities and asymmetric *** this context,we demonstrate the influence of perturbations on the frequency splitting of the *** generate higher-order exceptional points in a simple and robust way,a mirror-induced asymmetric backscattering approach is *** addition to the exceptional-point enhanced sensing capabilities of such systems,also a cavity-selective sensitivity is achieved for particle *** results are motivated by an effective Hamiltonian description and verified by full numerical simulations of the dielectric structure.

关键词： structure exceptional splitting

Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

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Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen Erik jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

Mechanical circulatory support in cardiogenic shock and post-myocardial infarction mechanical complications

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Journal of Geriatric Cardiology 2022年第2期19卷 130-136页

作者： Daniel Rob jan Bělohlávek nd Department of Medicine-Department of Cardiovascular Medicine First Faculty of MedicineCharles University and General University HospitalPragueCzech Republic

Despite advanced therapies,the mortality of patients with myocardial infarction(MI)complicated by cardiogenic shock(CS)remains around 50%.Mechanical complications of MI are rare nowadays but associated with high mortality in patients who present with *** treatment strategies and mechanical circulatory support(MCS)devices have been increasingly used to improve the grim prognosis of refractory *** article discusses current evidence regarding the use of MCS in MI complicated by CS,ventricular septal rupture,free wall rupture and acute mitral *** selection should be tailored according to the cause and severity of *** MCS initiation and multidisciplinary team cooperation is mandatory for good *** associated bleeding remains a major complication and an obstacle to better *** prospective randomized trials will improve current knowledge regarding MCS indications,timing,and patient selection in the coming years.

关键词： mortality infarction rupture

ARIMA模型在高值易波动药品需求预测中的应用

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医院管理论坛 2024年第2期41卷 59-63,88页

作者：王臣建周红萍杭州市儿童医院

目的应用ARIMA模型建立适合高值易波动药品需求预测的最优模型,以此构建预测平台,持续捕捉高值易波动药品的需求走势。方法结合ABC分类法和季节系数分类法从我院药品目录中筛选出高值易波动药品,根据2014一2022年的药品消耗数据,以BIC... 详细信息

目的应用ARIMA模型建立适合高值易波动药品需求预测的最优模型,以此构建预测平台,持续捕捉高值易波动药品的需求走势。方法结合ABC分类法和季节系数分类法从我院药品目录中筛选出高值易波动药品,根据2014一2022年的药品消耗数据,以BIC信息准则最小原则依次确定各品种的最优ARIMA模型,遵循ARIMA原理完成批量预测平台在Excel中的构建。结果筛选出51种高值易波动药品,在2022年的药品消耗金额中占50.82%,ARIMA模型拟合度指标平稳R方和平均绝对百分比误差获得理想数值,残差和参数分别通过白噪声检验和显著性检验,模型通过可持续性判断,批量预测平台搭建成功。结论ARIMA模型可应用于高值易波动药品需求走势的判断,基于ARIMA模型的批量预测平台能够高效、准确、持续服务于此类药品采购计划的执行。

关键词：高值易波动药品 ARIMA模型 ABC分类法药品采购

Investigating the use cases of a novel heat battery in Dutch residential buildings

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建筑模拟(英文) 2023年第9期16卷 1675-1689页

作者： Shuwei Wang Pieter-jan Hoes jan L.M.Hensen Olaf C.G.Adan Pim A.J.Donkers Department of the Built Environment Eindhoven University of TechnologyEindhovenP.O.Box 5135600 MB Eindhoventhe Netherlands Department of Applied Physics Eindhoven University of TechnologyEindhovenP.O.Box 5135600 MB Eindhoventhe Netherlands TNO Materials Solutions P.O.Box 62355600 HE Eindhoventhe Netherlands Cellcius BV Horsten 15612 AXEindhoventhe Netherlands

Recent advances in thermochemical storage technology have introduced a novel closed-loop thermal energy storage(TES)system,known as the heat battery(HB),which is believed to have great potential for aiding the energy transition in the built environment because of its higher energy density and neglectable storage loss compared to conventional TES *** order to investigate the potential use cases of the HB and provide practical feedback for its further development,this research employs a simulation-based approach to analyze its influence on building performance in various use cases within Dutch residential *** including the homeowner,distribution system operator,and district heating system operator are identified,and a preliminary list of use cases is defined based on relevant literature and input from the HB *** simulation approach is conducted to predict key performance indicators for each *** Kruskal-Wallis test was employed to sort and scrutinize the simulation outcomes and discern the significance of each use case *** findings demonstrated that the HB holds the potential to diminish both the operational energy cost by up to 30%for the homeowners and the peak heating load transmitted from the building to the district heating system.

关键词： thermochemical storage building performance simulation use case solar energy demand-side management