Selective CO_(2)Electroreduction to Multi-Carbon Products on Organic-Functionalized CuO Nanoparticles by Local Micro-Environment Modulation

Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO_(2)reduction reaction(CO_(2)RR)toward multi-carbon(C2+)products,primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO_(2)/CO concentration at the electrode.Building upon this approach,we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO_(2)RR to C_(2+)in a neutral electrolyte.Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules(HEB-CuO NPs),a remarkable C_(2+)Faradaic efficiency of nearly 90%was achieved at an unprecedented current density of 300 mA cm^(-2),and a high FE(>80%)was maintained at a wide range of current densities(100-600 mA cm^(-2))in neutral environments using a flow cell.Furthermore,in a membrane electrode assembly(MEA)electrolyzer,86.14%FEC2+was achieved at a partial current density of 387.6 mA cm^(-2)while maintaining continuous operation for over 50 h at a current density of 200 mA cm^(-2).In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K⋅H2O water increased the probability of intermediate reactants(CO)interacting with the surface,thereby promoting efficient C-C coupling and enhancing the yield of C_(2+)products.This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C_(2+)production.

Effects of different irrigation methods on micro-environments and root distribution in winter wheat fields

The irrigation method used in winter wheat fields affects micro-environment factors, such as relative humidity（RH） within canopy, soil temperature, topsoil bulk density, soil matric potential, and soil nutrients, and these changes may affect plant root growth.An experiment was carried out to explore the effects of irrigation method on micro-environments and root distribution in a winter wheat field in the 2007–2008 and 2008–2009 growing seasons.The results showed that border irrigation（BI）, sprinkler irrigation（SI）, and surface drip irrigation（SDI） had no significant effects on soil temperature.Topsoil bulk density, RH within the canopy, soil available N distribution, and soil matric potential were significantly affected by the three treatments.The change in soil matric potential was the key reason for the altered root profile distribution patterns.Additionally, more fine roots were produced in the BI treatment when soil water content was low and topsoil bulk density was high.Root growth was most stimulated in the top soil layers and inhibited in the deep layers in the SDI treatment, followed by SI and BI, which was due to the different water application frequencies.As a result, the root profile distribution differed, depending on the irrigation method used.The root distribution pattern changes could be described by the power level variation in the exponential function.A good knowledge of root distribution patterns is important when attempting to model water and nutrient movements and when studying soil-plant interactions.

3D numerical simulation of avascular tumour growth:effect of hypoxic micro-environment in host tissue

A three-dimensional （3D） mathematical model of tumour growth at the avascular phase and vessel remodelling in host tissues is proposed with emphasis on the study of the interactions of tumour growth and hypoxic micro-environment in host tissues. The hybrid based model includes the continuum part, such as the distributions of oxygen and vascular endothelial growth factors （VEGFs）, and the discrete part of tumour cells （TCs） and blood vessel networks. The simulation shows the dynamic process of avascular tumour growth from a fewinitial cells to an equilibrium state with varied vessel networks. After a phase of rapidly increasing numbers of the TCs, more and more host vessels collapse due to the stress caused by the growing tumour. In addition, the consumption of oxygen expands with the enlarged tumour region. The study also discusses the effects of certain factors on tumour growth, including the density and configuration of pre- existing vessel networks and the blood oxygen content. The model enables us to examine the relationship between early tumour growth and hypoxic micro-environment in host tissues, which can be useful for further applications, such as tumour metastasis and the initialization of tumour angiogenesis.

Packaging Bags with the Function of Micro-environment Modification

Three kinds of packaging bags composited with barrier film and moisture absorbents were designed in order to find out how to create an internal micro-environment with low O2content and relative humidity( RH). Peanuts with different moisture contents were filled into packaging bags and stored in an environmental chamber for a certain period of time. An RH recorder was sealed in each bag and the RH inside the bag was recorded. The moisture contents of peanuts before and after storage were measured as well.It is found that peanuts with moisture content of 13% can reduce O2content inside the bag by the aerobic respiration,achieving the self modified atmosphere packaging( MAP) effect. A microenvironment with lower RH can be created by using super-absorbent fiber( SAF) or mineral bag as the moisture absorbent. The moisture contents of peanuts stored in the bags with SAF and mineral bag as moisture absorbent decreased from 13% to 10. 5%and 11. 3%,respectively. SAF is a promising material of packaging bags composited with barrier film,in which a low RH and high CO2content can be created.

Effects of micro-environmental conditions and forest disturbance on the establishment of two Andean palms in Ecuador

The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.

Micro-environmentally Restricted Yeast Cell Growth within Ca-alginate Microbeads

Micro-environmental restriction effects to yeast cell growth obtained within Ca-alginate microbeads are considered. It is complex phenomenon influenced by: (1) relaxation of expanded polymer network around the cellular clusters, (2) forces generated by cell growth inside the beads and (3) interactions between solvent, network parts and cells. The resulting effects are measured experimentally by estimating volume of microbeads and yeast cell concentration as function of time of cultivation. Comparative analysis of dynamics of cell growth and increase of microbead volume through four regimes indicates that reversible and irreversible local structural changes of Ca-alginate hydrogel induces micro-environmental restrictions to cell growth. The mechanism of restrictions includes both mechanical and electrostatic effects.

The Construction of Micro-Environment in the College English Learning Based on the Rogers＇ Humanistic Teaching Theory

A small English class can be called as a micro-environment for English study. In this small micro-environment, the relationship between teachers and students is subtle. How to achieve the good interaction and create a good micro-environment in English class between teachers and students is very important for developing students＇ learning ability. This thesis is based on Rogers＇ humanistic teaching theory, which uses questionnaires, inteview and comparative analysis to analyze the current situation of micro-environment in college English learning. It discusses the construction of micro-environment in college English learning based on Rogers＇ humanistic teaching theory and the ways to construct it from software conditions （roles of teachers and students, relationship between teachers and students, the classroom atmosphere） and hardware conditions（teaching resources, a classroom）.

Revealing the role of electrode potential micro-environments in single Mn atoms for carbon dioxide and oxygen electrolysis

Elucidation the relationship between electrode potentials and heterogeneous electrocatalytic reactions has attracted widespread attention.Herein we construct the well-defined Mn single-atom(MnSA)catalyst with four N-coordination through a simple thermal pyrolysis preparation method to investigate the electrode potential micro-environments effect on carbon dioxide reduction reactions(CO_(2)RR)and oxygen reduction reactions(ORR).MnSA catalysts generate higher CO production Faradaic efficiency of exceeding 90%at-0.9 V for CO_(2)RR and higher H_(2)O_(2)yield from 0.1 to 0.6 V with excellent ORR activity.Density functional theory(DFT)calculations based on constant potential models were performed to study the mechanism of MnSA on CO_(2)RR.The thermodynamic energy barrier of CO_(2)RR is lowest at-0.9 V vs.reversible hydrogen electrode(RHE).Similar DFT calculations on the H_(2)O_(2)yield of ORR showed that the H_(2)O_(2)yield at 0.2 V was higher.This study provides a reasonable explanation for the role of electrode potential micro-environments.

Integrated and dual-responsive lipopeptide nanovector with parallel effect to tumor and micro-environment regulation by efficient gene and drug co-delivery

The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA)/RVA nano-vectors can sequentially respond to pH&redox stimuli,and guarantee efficient therapeutic gene delivery and control release of all-trans retinoic acid.The design provides a facile but promising strategy to treat refractory cancers.

Advances in the understanding of the intestinal micro-environment and inflammatory bowel disease

The human gastrointestinal tract accommodates an entire micro-environment for divergent physiologic processes,the dysbiosis of this micro-ecology has a strong inter-action with the pathogenesis of inflammatory bowel disease(IBD).In the past few years,with the advances in the understanding of microbiome,its metabolites and further application of next generation sequencing,analysis of dynamic alteration of gut micro-environment was realized,which provides numerous information beyond simple microbiota structure or metabolites differences under chronic colitis status.The subsequent intervention strategies targeting the modulation of intestinal micro-environment have been explored as a potential therapy.In this review,we will summarize the recent knowledge about multi-dimensional dysbiosis,the inter-action between fungus and bacteria under inflamed mucosa,and the clinical application of probiotics and fecal microbiota transplantation as a promising therapeutic approach in IBD.

Impact of micro-environmental factors on survival, reproduction and distribution of Oncomelania hupensis snails

Background:Schistosomiasis japonica is a chronic parasitic disease that seriously harms people's health.Oncomelonia hupensis is the only intermediate host of Schistosoma japonicum.Jhe micro-environmental factors surrounding the snail have a great impact on the survival,growth and reproduction of 0.hupensis,but there are few relevant systematic analyses until the present.This scoping review aims to identify and summarize the micro-environmental factors that greatly affect 0.hupensis,and to find gaps in research thus to provide directions for future in-depth studies.

Sculpturing solid polymer spheres into internal gridded hollow carbon spheres under controlled pyrolysis micro-environment

Porous carbon spheres with an internal gridded hollow structure and microporous shell have always been attractive as carbon hosts for electrochemical energy storage. Such carbon hosts can limit active species loss and enhance electronic conductivity throughout the entire framework. Herein, a synthesis approach of internal gridded hollow carbon spheres is developed from solid polymer spheres rather than originally gridded polymer spheres under a controlled pyrolysis micro-environment. The crucial point of this approach is the fabrication of a silica fence around solid polymer spheres, under which the free escaping of the pyrolysis gas will be partly impeded, thus offering a reconstitution opportunity for an internal structure of solid polymer spheres. As a result, the interior of carbon spheres is sculptured into a gridded hollow structure with microporous skin. Furthermore, the size and density of carbon-bridge grids can be modulated by altering the crosslinking degree of polymer spheres and varying pyrolysis conditions. Such gridded hollow carbon spheres show good performance as sulfur hosts for Li-S battery.

Investigation of a root zone heating system for greenhouse seedling and its effects on micro-environment

Under the extremely cold climatic condition,crops have to survive severe heat stress conditions,even if they are being kept in greenhouses.In the winter and spring of North China,the air and soil temperature is low inside the greenhouse,and when using a traditional heating system,the energy consumption is high.This paper reports on a study of different design solutions for a root zone heating system based on a kind of low temperature radiation material.Root zone heating systems offer increasing crop quality and productivity.A novel type of heat preservation and root zone heating system was applied in greenhouse seedling.And through multiple experiments,the effect of the root zone heating system on the ambient environment and seedbed surface was studied,and the heat preservation effect and heating uniformity were discussed.Results show that single-layer film covering on the root zone heating system can make the average temperature at night increase 1°C.And the average seedbed surface and substrate temperature can increase 11.3°C and 5.2°C,respectively.In conclusion,the root zone heating system can effectively improve the environmental temperature of seedling and the uniformity of heating is high,which provides a strong guarantee for high-quality seedling cultivation.

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

公安院校食药环微专业实验室建设与课程设计研究与探索

微专业作为一种跨学科专业教育模式,以灵活、开放的模式构筑学生跨学科专业素养。以食药环犯罪治理微专业核心课程之一食药环犯罪涉案物品检测鉴定为例,对双一流背景下公安院校微专业实验室的建设思路与总体目标进行了分析。从实验项目设置、实验室建设与管理方案、实验室科研创新方向等方面,对食药环微专业实验室建设思路与实验课程设计进行了探讨。

基于扎根理论的社区环境设施微更新设计策略

在城市更新活动逐渐呈现出社区转向特征的背景下,研究社区环境设施微更新的策略框架与构成要素,旨在为社区环境设施的更新设计提供系统的指导,从而更好推动社区环境设施的可持续发展。基于扎根理论的研究方法,对社区环境设施设计的典型案例进行归纳性编码,提出“设施单体改造、环境氛围重塑、民本精神融入与社群协同管理”四个方面策略,为探究、分析与实施社区环境设施微更新提供了系统性的策略指导。

地表水环境中微(纳米)塑料污染防控面临的挑战

微(纳米)塑料因其可在水体、沉积物、土壤等环境介质中长期存在并危害生态环境,且在环境中难降解的特性已成为一种新污染物。根据国内地表水环境中微(纳米)塑料的分布、来源和生态毒性效应的相关研究发现,地表水环境中微(纳米)塑料的来源繁杂,直接来源主要包括个人护理品、工农业制备、各类垃圾不当处置等;间接来源为污水处理厂的污水排放、地表径流、原始塑料的风化降解等。微(纳米)塑料的生态毒性组成复杂,除其本身对于生物体的生化胁迫外,还易与其他污染物形成复合污染,对水生生物产生交互效应。因此,研究治理地表水环境微(纳米)塑料污染已刻不容缓,本文可为地表水环境中微(纳米)塑料污染防控和生态风险研究提供理论参考。

基于可调谐激光技术的C_(4)F_(7)N气体中微水含量检测装置的研制

C_(4)F_(7)N气体是一种代替SF6的新型电气设备环保绝缘气体。C_(4)F_(7)N气体作为绝缘气体在高压设备中使用时,与SF6设备具有类似的问题,气体的质量影响着设备的正常运行。尤其当C_(4)F_(7)N气体中水分含量超标时,极易引起设备放电降低设备绝缘性能等问题的出现。因此研发针对使用C_(4)F_(7)N气体的运维检测设备就显得尤为重要。文中主要研究可调谐激光红外吸收光谱法对C_(4)F_(7)N中微水含量的定量检测技术。研究了可调谐激光的光谱理论、谐波检测原理和水分的红外吸收特性,介绍了在C_(4)F_(7)N为背景气体的情况下对微水检测精度的影响。其次对TDLAS结构设计、硬件设计及选型进行了介绍。选用DFB激光器,设计制作光电转换模块、光源驱动模块、红外多次反射池以及电路和软件部分,研制出可调谐激光基于C_(4)F_(7)N气体中微水检测装置,去除干扰组分影响,提高微水检测精度,可检测至1μL/L的低限值。装置性能检测结果表明,满足标准要求,定量检测微水准确性高,有利于正确判断设备运行状态。

机器学习辅助光谱分析技术在环境微/纳塑料研究中的应用

微/纳塑料在环境中广泛存在,威胁着全球生态系统的平衡和稳定,因此有必要确定和评估微/纳塑料的环境赋存特征、环境行为和效应以及生态毒性效应。然而微/纳塑料具有的低浓度、小尺寸及容易吸附其他物质等特点,为其在复杂环境基质中的分析带来了巨大挑战。大多数分析方法在提供环境样本中微/纳塑料的定性定量信息方面存在成本高、准确性差、时间效率低等问题,而具有无损、高效、操作方便等优点的光谱分析技术可以弥补这些方法的不足。但采集的微/纳塑料光谱信号可能会受到环境样本中复杂成分的背景噪声干扰,亟需采用智能化手段提高分析的准确性和效率。机器学习具有强大的数据处理和自动化分析能力,准确性高、应用性广,适用于复杂光谱数据的分类和解析,将机器学习与光谱分析技术相结合有望成为微/纳塑料分析的可靠方法。首先对常用的机器学习辅助光谱分析技术进行综述,然后系统性地讨论了机器学习辅助光谱分析技术在微/纳塑料的环境赋存特征、环境行为和效应、生态毒理效应等研究中的应用,最后对该技术的发展前景进行了总结和展望。机器学习辅助光谱分析技术有望为环境中微/纳塑料的生态环境健康风险评估和污染防治提供重要数据支持。

铸铝叉架环境适应性改进研究

铸铝叉架是某舱外天线设备的重要结构件,其工作环境为高湿、高低温交替、高盐雾的海洋环境,因此要求铸铝叉架具备良好的防腐、耐高温、低温的性能。某天线设备的铸铝叉架在多年的使用后局部出现了腐蚀情况,其环境适应性已不能满足设备的使用要求。本文针对铸铝叉架进行环境适应性改进研究,对其材料、表面处理进行改进,并且对改进后的铸铝叉架进行了性能验证。通过高低温湿热试验、盐雾以及霉菌试验,结果表明,改进后铸铝叉架的环境适应性满足海洋环境的使用要求。