Single-atom zinc catalyst for co-production of hydrogen and fine chemicals in soluble biomass solution

Single-atom photocatalysts(SAPCs)have attracted great interests due to their remarkable atom utilization efficiency,excellent activity,and selectivity,yet no application in synchronous biorefinery and water splitting.Here,efficient SAPCs based on atomically dispersed Zn atoms on carbon nitride(named Zn-mCN)were produced.Experiments verified that Zn-mCN has widened adsorption range of visible-light and lowered ability of electron-hole recombination,leading to excellent photocatalytic redox activity for synchronous biorefinery and water splitting to co-produce lactic acid(selectivity up to 91.0%)and hydrogen(-15898.8μmolg^(-1)h^(-1)).This system has excellent universality for small-molecule monosaccharides and macromolecular xylan.Poisoning experiments showed that h^(+),1O2,·O_(2)-and·OH can promote the simultaneous production of lactic acid and hydrogen.This work realized full utilization of whole redox reaction and provided a novel strategy for efficient and concomitant production of hydrogen and value-added chemicals from biomass-derived feedstocks aqueous solutions.

A method for identifying coalbed methane co-production interference based on production characteristic curves: A case study of the Zhijin block, western Guizhou, China

Efficient detection of coalbed methane(CBM) co-production interference is the key to timely adjusting the development plan and improving the co-production efficiency. Based on production data of six typical CBM co-production wells in the Zhijin block of western Guizhou Province, China, the production characteristic curves, including production indication curve, curve of daily water production per unit drawdown of producing fluid level with time, and curve of water production per unit differential pressure with time have been analyzed to explore the response characteristics of co-production interference on the production characteristic curves. Based on the unit water inflow data of pumping test in coal measures, the critical value of in-situ water production of the CBM wells is 2 m^(3)/(d·m). The form and the slope of the initial linear section of the production indication curves have clear responses to the interference, which can be used to discriminate internal water source from external water source based on the critical slope value of 200 m^(3)/MPa in the initial linear section of the production indication curve. The time variation curves of water production per unit differential pressure can be divided into two morphological types: up-concave curve and down-concave curve. The former is represented by producing internal water with average daily gas production greater than 800 m^(3)/d, and the latter produces external water with average daily gas production smaller than 400 m^(3)/d. The method and critical indexes for recognition of CBM co-production interference based on the production characteristic curve are constructed. A template for discriminating interference of CBM co-production was constructed combined with the gas production efficiency analysis, which can provide reference for optimizing co-production engineering design and exploring economic and efficient co-production mode.

Knowledge flow analysis of knowledge co-production-based climate change adaptation for lowland rice farmers in Bulukumba Regency,Indonesia

To increase the resilience of farmers’livelihood systems,detailed knowledge of adaptation strategies for dealing with the impacts of climate change is required.Knowledge co-production approach is an adaptation strategy that is considered appropriate in the context of the increasing frequency of disasters caused by climate change.Previous research of knowledge co-production on climate change adaptation in Indonesia is insufficient,particularly at local level,so we examined the flow of climate change adaptation knowledge in the knowledge co-production process through climate field school(CFS)activities in this study.We interviewed 120 people living in Bulukumba Regency,South Sulawesi Province,Indonesia,involving 12 crowds including male and female farmers participated in CFS and not participated in CFS,local government officials,agriculture extension workers,agricultural traders,farmers’family members and neighbors,etc.In brief,the 12 groups of people mainly include two categories of people,i.e.,people involved in CFS activities and outside CFS.We applied descriptive method and Social network analysis(SNA)to determine how knowledge flow in the community network and which groups of actors are important for knowledge flow.The findings of this study reveal that participants in CFS activities convey the knowledge they acquired formally(i.e.,from TV,radio,government,etc.)and informally(i.e.,from market,friends,relatives,etc.)to other actors,especially to their families and neighbors.The results also show that the acquisition and sharing of knowledge facilitate the flow of climate change adaptation knowledge based on knowledge co-operation.In addition,the findings highlight the key role of actors in the knowledge transfer process,and key actors involved in disseminating information about climate change adaptation.To be specific,among all the actors,family member and neighbor of CFS actor are the most common actors in disseminating climate knowledge information and closest to other actors in the network;agricultural trader and family member of CFS actor collaborate most with other actors in the community network;and farmers participated in CFS,including those heads of farmer groups,agricultural extension workers,and local government officials are more willing to contact with other actors in the network.To facilitate the flow of knowledge on climate change adaptation,CFS activities should be conducted regularly and CFS models that fit the situation of farmers’vulnerability to climate change should be developed.

How Does the Government Facilitate the Co-Production of Digital Public Safety Services?——Based on Empirical Evidence from Shenzhen

The application of big data technology provides support for the co-production of public safety services.Existing research often focuses on how technology influences co-production,but lacks attention to the key actors that drive co-production and the mechanisms that facilitate it.This study examines the role of government in the digital co-production of public safety services,using the practice of Shenzhen as a case study.Shenzhen has built 125 information systems based on over 100 billion pieces of big data,forming a model of digital safety service co-production.The study reveals three types of digital co-production,characterized by"government-business joint planning,passive participation of businesses and the public,and active cooperation among government,businesses,and the public"in the"design-production-application"stages.The study shows that the government is not only a co-producer but also a proactive actor in activating the willingness of non-governmental entities to participate.Local governments mobilize non-governmental participation through three mechanisms:empowerment,profit enhancement,and value co-creation.The"power-interest-value"paradigm is applicable for analyzing the co-production of public services and helps to explain the transformation mechanisms of co-production behavior.

Coalbed methane desorption characteristics controlled by coalification and its implication on gas co-production from multiple coal seams

In this work,CH4 isothermal adsorption measurements were carried out on 64 coal samples collected from western Guizhou Province of China,and the coalbed methane(CBM)desorption processes were quantitatively analyzed.The results show that the Langmuir volume and the Langmuir pressure are controlled by coalification,and tend to increase as the vitrinite reflectance changes from 0.98% to 4.3%.Based on a division method of CBM desorption stages,the CBM desorption process were divided into four stages(inefficient,slow,fast and sensitive desorption stages)by three key pressure nodes(the initial,turning and sensitive pressures).The fast and sensitive desorption stages with high desorption efficiency are the key for achieving high gas production.A theoretical chart of the critical desorption pressure(P_(cd))and its relationship with different pressure nodes was established.The higher-rank coals have the higher initial,turning and sensitive pressures,with larger difference between pressure nodes.Most CBM wells only undergo partial desorption stages due to the differences in P_(cd) caused by the present-gas content.Under the same gas content conditions,the higher the coal rank,the less desorption stages that CBM needs to go through.During coalbed methane co-production from multiple coal seams within vertically superposed pressure systems,the reservoir pressure,the P_(cd),the initial working liquid level(WLL)height,and coal depth are key factors for evaluating whether coal seams can produce CBM simultaneously.It must be ensured that each production layer enters at least the fast desorption stage prior to that the WLL was lower than the depth of each layer.Only on this basis can all layers achieve the maximum gas production.

合供与敏捷治理

“合供”是公共服务提供的新模式,但已有研究并没有对合供何以促进公共价值创造进行充分的解释和研究。从“敏捷治理”范式出发,可以为合供何以促进公共价值创造提供一个理论分析框架。从发展动态能力和激发迭代创新等角度出发对合供促进敏捷治理的机制和实践路径进行分析,阐释合供何以促进敏捷治理的实现,及其如何通过增强动态能力、促进迭代创新来提升公共部门敏捷治理等重要理论问题。从“敏捷治理”范式出发,分析合供促进公共价值创造,对于进一步深化合供和公共价值创造研究具有重要的理论和实践意义。

源流耦合:乡村公共文化治理中合作生产的生成机制——基于乡村春晚的案例分析

“身有所栖”而“心无所寄”现象是乡村治理工作中的突出问题,以需求回应性和农民主体性为特征的合作生产成为解决上述问题的关键模式。通过对乡村春晚案例的研究发现,乡村公共文化治理中合作生产的生成是由在特定时刻汇合在一起的多种因素共同作用的结果,即文化源流推动下文化之窗打开,通过文化源流、行政源流和乡土源流的两两局部耦合开启行政之窗和乡土之窗,在此基础上建立起政府与农民之间的资源依赖关系,实现三者的全部耦合开启合作之窗,进而在领导注意力分配的驱动下生成。乡村公共文化合作生产生成机制为理解中国情境下的乡村治理和乡村振兴提供了新的视角。

社区志愿服务共同生产:内涵逻辑及过程机理

在社区“志愿失灵”、居民“弱参与”以及志愿服务供给与实际动态需求错配等现实背景下,创新社区志愿服务提供模式成为学术界广泛关注的议题。从共同生产理论出发,在明确社区志愿服务共同生产内涵逻辑的基础上,进一步从服务发起、资源链接、主体交互、价值创造以及评价反馈等阶段揭示其过程机理。社区志愿服务蕴含丰富的共同生产特征,在组织志愿服务过程中,我们应转变观念,意识到开放的合作系统是社区志愿服务共同生产的行动框架;多主体协作生产是社区志愿服务共同生产的发展方向;服务导向是社区志愿服务共同生产的重要理念;志愿服务共同生产过程中的社区居民不仅是志愿服务的接受者和受益者,同时也是服务的参与者和共同生产者。

数智治理何以触发基层公共服务合作生产价值共损?——以S市社区新基建为例

以数字技术助推基层治理创新是公共服务改革的重要方向。数智治理为合作生产中的主体间社会互动和资源整合提供了前提条件,但也因其发展尚不成熟,为基层实践带来资源滥用、人居矛盾、价值冲突、交付悖论等诸多风险威胁和价值共损困境。基于服务生态系统视角,以S市社区新基建案例为研究对象,探究数智治理触发基层公共服务合作生产价值共损的过程机理。研究发现:数智治理过程中参与主体特征差异、技术工具缺陷和制度体系失灵是引发基层公共服务合作生产价值共损的关键要素,且三种要素之间彼此纠缠互锁。其中,主体特征差异与技术工具缺陷的交互路径、主体特征差异与制度体系失灵的交互路径,会受到参与者价值损坏情结的嵌入调节。上述多重要素与路径共同导致基层合作生产服务生态系统中的社会互动和资源整合发生失衡,最终触发多元主体价值共损。

Towards a Climate Service for the Tea Industry:A Collaborative Approach between the UK and China

Tea is an important global commodity,with important tea-growing regions spanning across South America,Africa,and Asia,and burgeoning smaller-scale and artisanal tea production in the UK and Europe.In each of these regions,the quality and quantity of tea production,with their economic and social consequences,are highly sensitive to variations in the climate on both short-term weather,seasonal and climate change timescales.The provision of tailored climate information in a timely and accessible manner through the development,delivery and use of climate services can help tea-farmers and other relevant stakeholders better understand the impacts of climate variability and climate change on decision-making and a range of adaptive actions.This paper presents an overview of the Tea-CUP project(Co-developing Useful Predictions),a joint initiative between UK and Chinese partners,which aims to develop and implement solutions for improving robust decision-making.Co-production principles are core,ensuring that the resultant climate services are usable and useful;users'needs are met through close engagement and joint research and decision-making.The paper also reports on the exchange of knowledge and experiences,such as between tea growers in China and the UK,which has resulted from this collaborative work,fostering global knowledge sharing,enriching understanding,and driving innovation by integrating diverse perspectives and expertise from different countries.This is an unintended but valuable side-effect of the collaborative approach taken and highlights the benefits of a highly relational and multidisciplinary approach to climate services development that will inform future work in the field.

“兜底+助推”:社区转型共同生产模式及其生成机制——以S镇“村改居”为例

“村改居”后续治理难题和可持续发展困境引发了对社区转型依靠力量、动员机制、推进策略等问题的反思,亟须构建一种兼容党政主导和居民参与的社区转型共同生产模式。案例表明,“兜底+助推”的共同生产模式催生了“村改居”的整体转型。党建引领下的体制赋能和资源支持机制为搬迁动员提供了兜底保障;组织协商和信任塑造机制加强了多方互动,助推了共同生产的发展。体制赋能、资源支持、组织协商、信任塑造等四大机制互为补充,共同形塑、巩固和维系了“党政链接社会”的共同生产方式。从根源来看,社区价值共创是社区深度转型和持续发展的关键。从过程视角探究中国情境下社区转型共同生产的模式、机制和策略,有助于拓展共同生产研究和丰富地方治理工具。

LNG接收站BOG回收与提氦联产工艺设计及优化

为了解决当前BOG回收工艺以及BOG提氦工艺存在回收率低和高能耗等问题,提出一种联产工艺,将LNG接收站BOG回收工艺与BOG提氦工艺相结合。使用HYSYS模拟单一工艺和联产工艺,分析影响工艺综合能耗及粗氦浓度的关键参数。保持粗氦浓度为92.61%,以综合能耗最小为优化目标,结合响应面法和遗传算法对关键参数进行优化,得到最优参数:BOG压缩机出口压力为600 kPa,低压泵出口压力700 kPa,海水泵出口压力4 000 kPa,深冷塔进料温度为-150℃,深冷塔进料压力为1 000 kPa。与单一工艺相比,该联产工艺有明显的节能优势,综合能耗减少16.17%,BOG回收率达到84.21%,粗氦的回收率和浓度分别达到95.83%和92.61%。结论表明:该联产工艺在能耗和投资成本方面具备明显的优势。

氮气双膨胀制冷提氦联产乙烷工艺设计与优化

国内某气田天然气中乙烷和氦气含量(物质的量分数)逐年升高,回收价值凸显。提出了一种氮气双膨胀制冷提氦联产乙烷工艺,采用HYSYS软件对该工艺进行了流程模拟,并对工艺流程的关键参数(低温分离器温度、脱甲烷塔塔顶回流比、二级提氦塔进料温度、二级提氦塔塔顶回流比、氮气膨胀端入口压力、氮气膨胀端出口压力和氮气制冷剂流量)对工艺指标的影响规律开展了研究。基于最优化理论,以C_(2)收率最大和二次粗氦浓度最大时装置总能耗最小为目标,采用Back Propagation(BP)神经网络算法对关键参数进行了寻优。结果表明,装置总能耗主要受低温分离器温度、氮气膨胀端出口压力和氮气制冷剂流量影响,C_(2)收率主要受低温分离器温度和脱甲烷塔塔顶回流比影响,氦收率主要受二级提氦塔进料温度影响。关键参数最佳组合为:低温分离器温度为-95.30℃,氮气制冷剂流量为1549.22 kmol/h,氮气膨胀端入口压力为3.25 MPa,氮气膨胀端出口压力为0.44 MPa,脱甲烷塔塔顶回流比为0.13,二级提氦塔进料温度为-150.57℃,二级提氦塔塔顶回流比为0.80。相比于优化前,优化后装置总能耗降低了1.46%,C_(2)收率提升了5.64%,二次粗氦浓度(物质的量分数)提升了1.81%。

漂浮式海上风电离网制氢联合仿真实验平台

海上风电制氢有助于解决海上风电消纳和远海输电难题,但目前的仿真缺乏海上环境对制氢影响的模拟,限制了相关研究与教学发展,因此亟需开发充分考虑海洋环境载荷的海上风电离网制氢仿真实验平台。该文将风机一体化仿真工具FAST和MATLAB/Simulink电力系统工具箱相结合,实现海上风机与发电机的联合仿真,在MATLAB内部通过设计接口实现电力系统与数学模型的两工具箱的联合仿真,以此构建两软件三工具箱联合的海上风电离网制氢一体化仿真实验平台。仿真结果表明,该平台能实现漂浮式海上风电离网制氢联合仿真,可为海上风电制氢有关研究和实验教学提供有力支撑。

基于片区统筹和三生融合的黄江镇村属工业建筑改造策略

在存量时代背景下,工业用地改造成为城市更新的重点,工业上楼是工业改造的创新发展模式。结合东莞市黄江镇工业建筑改造项目,介绍了工业建筑改造策略,表明工业上楼应以片区统筹的理念进行整体更新优化,建立“街坊-地块”统筹的改造模式,融合生产、生活、生态功能布局和设计。

国家天然气(页岩气)千亿立方米级产能基地共建共享模式

国家天然(页岩气)千亿立方米级产能基地建设是保障国家能源安全、支撑区域社会经济加快发展的重大战略。在借鉴油气共建共享成功经验基础上,构建了国家天然气(页岩气)千亿立方米级产能基地共建共享模式,提出了模式实施路径。研究结果表明:①国家天然气(页岩气)千亿立方米级产能基地建设涉及庞大的产业体系与多元主体不同利益诉求,需要以共建共享理念和系统工程思维为指引,立足多元主体与多维度要素协同构建共建共享模式。②模式实施五大路径:强化共建共享顶层战略设计,丰富发展政企共建共享方式,完善企业之间共建共享机制,畅通多元主体沟通协商渠道,健全共建共享应急预警体系。结论认为,该模式以战略视域统筹产能基地建设,能够实现对多元主体利益的有效协同,促进天然气(页岩气)资源开发利用与产业链价值提升,为带动区域社会经济发展并推进共同富裕提供有力支持。

微波加热下生活废纸和PE塑料共热解产气特性

以可燃生活垃圾中的主要成分——生活废纸和聚乙烯(polyethylene,PE)塑料为原料,采用微波加热,对纸张/PE共热解中产气释放过程、产气成分和产气率等特性的影响规律进行研究。实验结果表明:在600℃热解终温下,产气成分以CO、CO_(2)为主,约为35%~40%,其次为CH_(4)、H_(2),其他气体含量较低。随着微波功率的增加,热解产气各成分的产量都明显增加,且各产气析出温度及峰值温度向高温方向移动。随着物料中PE的混合比例增加,纸张/PE共热解产气率降低明显,焦油产率则明显增加,表明PE热解产物以焦油为主。在定热解终温的情况下,添加热解碳对热解产气成分的体积分数影响不大,但可有效提高热解产气量。

产品共创视角下考虑消费者参与创新的供应链定价与协调

随着互联网技术的发展以及后现代主义消费意识的形成,产品共创已经成为市场中越来越多企业的共同选择。在产品共创视角下,以单制造商和单零售商组成的二级供应链为背景,构建供应链集中式决策模型和分散式决策模型,比较分析两种模型下消费者参与制造商产品创新的程度与制造商促使消费者参与的能力水平两个变量对供应链各成员定价决策的影响,并采用两部定价、收益共享以及成本共担三种协调机制对供应链进行协调。研究表明,当消费者参与产品创新的程度不大于某一阈值时,产品最优售价、需求量以及供应链总利润均与消费者参与产品创新的程度以及制造商促使消费者参与的能力水平呈同向变动关系;两部定价、收益共享以及成本共担三种协调机制均可实现供应链帕累托改进,而且相较于其余两种协调机制,两部定价契约对供应链的协调效果更为明显。

三种动物粪便与甜高粱混合批次产甲烷潜能比较

为评估不同粪便对甜高粱原料利用率的影响,在温度为(37±0.5)℃、甜高粱与动物粪便的挥发性固体(VS)质量比为1∶1的条件下,比较了甜高粱与奶牛粪(SCM组)、猪粪(SPM组)和羊粪(SSM组)进行混合厌氧消化的产气性能,应用修正的Gompertz方程分析了甲烷产生的动力学过程。修正的Gompertz模型显示,各试验组相关系数R2=0.983~0.997,SCM组具有最大产甲烷速率(rm)78.37 m L/(g·d)(以VS质量计),较甜高粱原料组(SS组)提升了115.30%。在三个混合消化实验组中,SCM组具有最大的累积产沼气率、日产甲烷率和累积产甲烷率,分别为556.98、93.68和274.51 m L/g(以挥发性固体质量计)。SPM组具有61.60%的最大甲烷体积分数。SSM组的日产甲烷率较SS组降低了16.33%。SCM、SPM和SSM组的协同效应指数分别为26.15%、15.71%和28.24%。实验结果表明,SCM组更好地弥补了SS组具有高碳氮比的缺陷,实现底物间的优势互补,与SPM和SSM组相比,SCM组的累积产沼气率、日产甲烷率和累积产甲烷率更优。通过添加不同底物对产气率、产甲烷率和厌氧消化参数的比较,可为甜高粱在沼气工业中的利用提供理论依据。

AI时代的教育与评价

以ChatGPT为代表的AI技术发展对现有教育与评价体系提出挑战,并引发对教育模式与教育理念根本性变革的思考。在AI时代,对知识的了解与掌握已不再是学习的主要目的。以创新、创造、创业为内核的“三创教育”为面向未来的教育提供了一条新路径,其三个基本特征包括可个性化的学习、发现并解决真实问题/产品导向的学习、全球化的学习环境。AI为“三创教育”提供了切实可用的工具与实现方式。人机共生与共同演化(co-evolution)的时代已开启,教育工作者需要深入思考人与AI的关系,以及如何在AI时代实现教育公平和个人成长。