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Synthesis and evaluation of cationic polymeric micelles as carriers of lumbrokinase for targeted thrombolysis

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Asian Journal of Pharmaceutical Sciences 2019年第2期14卷 144-153页

作者： Yang Pan xiahui wang Zongning Yin Key Laboratory of Drug Targeting and Drug Delivery Systems West China School of Pharmacy Sichuan University

To achieve targeted thrombolysis, a targeted delivery system of lumbrokinase(LK) was constructed using RGDfk-conjugated hybrid micelles. Based on the specific affinity of RGDfk to glycoprotein complex of GP Ⅱ b/Ⅲ a expressed on the surface of membrane of activated platelet, LK loaded targeted micelles(LKTM) can be delivered to thrombus. The hybrid micelles were composed of polycaprolactone-block-poly(2-(dimethylamino) ethyl methacrylate)(PCL-PDMAEMA), methoxy polyethylene glycol-block-polycaprolactone(mPEG-PCL)and RGDfk conjugated polycaprolactone-block-polyethylene glycol(PCL-PEG-RGDfk). PCLPDMAEMA was synthesized via ring open polymerization(ROP) and atom transfer radical polymerization(ATRP). PCL-PEG-RGDfk was synthesized via ROP and carbodiimide chemistry. The prepared LKTM was characterized by dynamic light scattering(DLS) and transmission electron microscope(TEM). Colloidal stability assay showed the prepared LKTM was stable. Biocompatibility assay was performed to determine the safe concentration range of polymer. The assay of fluorescent distribution in vivo demonstrated that LKTM can be efficiently delivered to thrombi in vivo. Thrombolysis in vivo indicated the thrombolytic potency of LKTM was optimal in all groups. Notably, the laboratory mice treated with LKTM exhibited a significantly shorter tail bleeding time compared to those treated with LK or LK-loaded micelles without RGDfk, which suggested that the targeted delivery of LK using RGDfk-conjugated hybrid micelles effectively reduced the bleeding risk.

关键词： Targeted thrombolysis Lumbrokinase Polymeric micelles ATRP ROP

Kinematics and Path Following Control of an Articulated Drum Roller

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 888-899页

作者： Yongming BIAN Meng YANG Xiaojun FANG xiahui wang School of Mechanical Engineering Tongji UniversityShanghai 201804China

Automatic navigation of an articulated drum roller, which is an articulated steering type vehicle widely used in the construction industry, is highly expected for operation cost reduction and improvement of work effi- ciency. In order to achieve the path following control, considering that its steering system is articulated steering and two frames are articulated by an active revolute joint, a kinematic model and an error dynamic state-space equation of an articulated drum roller are proposed. Besides, a state- feedback control law based on Lyapunov stability theory is also designed, which can be proved to achieve the purpose of control by the analysis of stability. What＇s more, to evaluate the performance of the proposed method, simu- lation under the MATLAB/Simulink and experiments using positioning algorithm and errors correction at the uneven construction site are performed, with initial dis- placement error （-1.5 m）, heading error （-0.11 tad） and steering angle （-0.19 rad）. Finally, simulation and exper- imental results show that the errors and steering angle can decrease gradually, and converge to zero with time. Meanwhile, the control input is not saturated. An articu- lated drum roller can lock into a desired path with the proposed method in uneven fields.

关键词： Kinematics Path following controlArticulated drum roller Positioning algorithmPositioning errors correction

黄河流域水-能源-生态系统协同增效战略体系构建研究

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环境科学研究 2024年第1期37卷 11-23页

作者：迟妍妍王夏晖刘斯洋张丽苹王晶晶付乐许开鹏王金南生态环境部环境规划院黄河生态文明研究中心北京100041

黄河流域生态保护和高质量发展国家重大战略加快推进实施,流域水资源、能源、生态安全作为战略实施的核心要素、基础动力和约束性要求,三者形成互为基础、相互依存、彼此促进的有机整体.本文构建了水-能源-生态系统协同增效概念模型,评... 详细信息

黄河流域生态保护和高质量发展国家重大战略加快推进实施,流域水资源、能源、生态安全作为战略实施的核心要素、基础动力和约束性要求,三者形成互为基础、相互依存、彼此促进的有机整体.本文构建了水-能源-生态系统协同增效概念模型,评估了黄河流域水资源承载、生态系统质量、碳排放并揭示了其驱动因素,系统分析了黄河流域水-能源-生态系统之间的纽带关系,构建了黄河流域水-能源-生态系统协同增效战略体系.结果表明:(1)2021年黄河流域水资源严重超载,除青海省和四川省以外,其他7个省区水资源开发潜力很小;同时流域生态系统敏感脆弱、生态系统服务功能重要,极度、重度敏感区域面积占比共计52%,生态系统服务功能极重要、较重要区域面积占比共计63.2%.2005-2021年黄河流域CO_(2)排放量上升,但排放强度总体下降,青海省、甘肃省和山西省CO_(2)排放强度下降明显.(2)自然生态本底脆弱、天然河川径流量减少、供水量平稳但耗水量增加、用水结构不合理、上游用水效率不高、以煤为主的能源消费结构是导致黄河流域生态系统敏感、水资源超载、碳排放量增加的主要驱动因素.(3)黄河流域水-能源-生态系统相互依存、相互影响,具体表现在流域水量减少直接影响生态系统质量,干流人工化导致河流生态系统受损,水资源过度开发利用引发生态环境问题,忽略水资源承载的生态治理引发新问题,煤炭开采加剧水资源短缺造成生态恶化,能源利用效率较低不利于污染物和CO_(2)协同减排等方面.基于以上分析,提出以“刚性约束”为核心综合调控水资源、以“以水定绿”为核心实施一体保护修复、以“清洁低碳”为核心加快能源多元转型、以“联动增效”为核心推进流域协同治理、以“工程引领”为核心推动协同目标实现等对策措施.

关键词：黄河流域水-能源-生态系统协同增效生态保护高质量发展

S-scheme heterojunction of crystalline carbon nitride nanosheets and ultrafine WO_(3)nanoparticles for photocatalytic CO_(2)reduction

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Journal of Environmental Sciences 2024年第6期140卷 103-112页

作者： Gongjie Chen Ziruo Zhou Bifang Li xiahui Lin Can Yang Yuanxing Fang Wei Lin Yidong Hou Guigang Zhang Sibo wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFujian 350116China

Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting;however,their mission in light-driven CO_(2)conversion remains to be explored.In this work,crystalline carbon nitride(CCN)nanosheets of poly triazine imide(PTI)embedded with melon domains are fabricated by KCl/LiCl-mediated polycondensation of dicyandiamide,the surface of which is subsequently deposited with ultrafine WO_(3)nanoparticles to construct the CCN/WO_(3)heterostructure with a S-scheme interface.Systematic characterizations have been conducted to reveal the compositions and structures of the S-scheme CCN/WO_(3)hybrid,featuring strengthened optical capture,enhanced CO_(2)adsorption and activation,attractive textural properties,as well as spatial separation and directed movement of light-triggered charge carriers.Under mild conditions,the CCN/WO_(3)catalyst with optimized composition displays a high photocatalytic activity for reducing CO_(2)to CO in a rate of 23.0μmol/hr(i.e.,2300μmol/(hr·g)),which is about 7-fold that of pristine CCN,along with a high CO selectivity of 90.6%against H2formation.Moreover,it also manifests high stability and fine reusability for the CO_(2)conversion reaction.The CO_(2)adsorption and conversion processes on the catalyst are monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS),identifying the crucial intermediates of CO_(2)^(*)-,COOH^(*)and CO^(*),which integrated with the results of performance evaluation proposes the possible CO_(2)reduction mechanism.

关键词： Crystalline carbon nitride Photocatalysis CO_(2)reduction S-scheme WO_(3)

Contact angle and stability of interfacial nanobubble supported by gas monolayer

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Fundamental Research 2024年第1期4卷 35-42页

作者： Haichang Yang Yaowen Xing Fanfan Zhang xiahui Gui Yijun Cao Chinese National Engineering Research Center of Coal Preparation and Purification China University of Mining and TechnologyXuzhou 221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116China Henan Province Industrial Technology Research Institution of Resources and Materials Zhengzhou UniversityZhengzhou 450001China

Since solid-liquid interfacial nanobubbles(INBs)were first imaged,their long-term stability and large contact angle have been perplexing scientists.This study aimed to investigate the influence of internal gas density and external gas monolayers on the contact angle and stability of INB using molecular dynamics simulations.First,the contact angle of a water droplet was simulated at different nitrogen densities.The results showed that the contact angle increased sharply with an increase in nitrogen density,which was mainly caused by the decrease in solid-gas interfacial tension.However,when the nitrogen density reached 2.57 nm^(-3),an intervening gas monolayer(GML)was formed between the solid and water.After the formation of GML,the contact angle slightly increased with increasing gas density.The contact angle increased to 180°when the nitrogen density reached 11.38 nm^(-3),indicating that INBs transformed into a gas layer when they were too small.For substrates with different hydrophobicities,the contact angle after the formation of GML was always larger than 140°and it was weakly correlated with substrate hydrophobicity.The increase in contact angle with gas density represents the evolution of contact angle from macro-to nano-bubble,while the formation of GML may correspond to stable INBs.The potential of mean force curves demonstrated that the substrate with GML could attract gas molecules from a longer distance without the existence of a potential barrier compared with the bare substrate,indicating the potential of GML to act as a gas-collecting panel.Further research indicated that GML can function as a channel to transport gas molecules to INBs,which favors stability of INBs.This research may shed new light on the mechanisms underlying abnormal contact angle and long-term stability of INBs.

关键词： Interfacial tension Hydrophobicity Potential of mean force Gas density Molecular dynamics simulations

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农村生活污水资源利用:进展、困境与路径

农业资源与环境学报 2023年第5期40卷 1255-1264,I0002页

作者：王波何军车璐璐戴超郑利杰王夏晖生态环境部环境规划院农村环境保护中心北京100041 生态环境部环境规划院北京100041

当前,我国农村生活污水治理水平低与农业缺水并存,学界呼吁跳出单纯污水处理的传统思维,探索适度处理与资源利用相结合的新模式。近年来,我国农村生活污水治理工作得到重视、成效显著,但仍面临理念滞后、治理体系不完善、标准规范欠缺... 详细信息

当前,我国农村生活污水治理水平低与农业缺水并存,学界呼吁跳出单纯污水处理的传统思维,探索适度处理与资源利用相结合的新模式。近年来,我国农村生活污水治理工作得到重视、成效显著,但仍面临理念滞后、治理体系不完善、标准规范欠缺、系统谋划不足等问题。本文在梳理农村生活污水资源利用研究进展的基础上,分析其工作成效和现实困境,并分别从系统观念、考核办法、标准制(修)订、举措创新、试点示范等方面,提出资源利用实现路径,以期为我国农村生活污水治理提供技术支撑。

关键词：农村生活污水资源利用适度处理节能低碳实现路径

Thoughts and Practice of Ecological Protection and Restoration of Mountains, Rivers, Forests, Farmlands, Lakes and Grasslands

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Journal of Landscape Research 2020年第3期12卷 5-8页

作者： wang xiahui HE Jun wang Bo ZHANG Xiao Chinese Academy of Environmental Planning Beijing 100012China

The report of the 19th National Congress of the Communist Party of China stated that it was necessary to establish and practice the concept that lucid waters and lush mountains are invaluable assets,treat the ecological environment as life,and coordinate the management of mountains,rivers,forests,farmlands,lakes and grasslands.In recent years,China has organized a series of pilot projects for the ecological protection and restoration of mountains,rivers,forests,farmlands,lakes and grasslands,breaking the boundary between administrative divisions,departmental management and ecological elements,and implementing conservation and restoration oriented towards the improvement of ecosystem services,so as to solve the problem of the lack of overall planning for ecological protection and restoration projects and the separated management of ecological elements.This study systematically elaborated the theoretical basis and connotation characteristics of ecological protection and restoration of mountains,rivers,forests,farmlands,lakes and grasslands.It proposed the implementation path of ecological protection and restoration project of mountains,rivers,forests,farmlands,lakes and grasslands by taking the water source conservation area of Beijing-Tianjin-Hebei as a case,so as to provide reference for the implementation and decision-making management of ecological protection and restoration projects in various regions.

关键词： Mountains rivers forests farmlands lakes and grasslands Ecological protection and restoration Ecological service functions Ecological elements

产业发展对生态安全影响的预警技术研究框架初探

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生态经济 2022年第1期38卷 186-192,201页

作者：牟雪洁饶胜张箫王夏晖黄金生态环境部环境规划院北京100012

总结了当前我国生态安全及预警相关概念,对比分析了现有生态安全预警思路与方法,以生产空间为研究对象,从产业发展导致的生态环境问题角度出发,研究提出了产业发展对生态安全影响预警的技术框架,建议针对资源消耗型、环境破坏型区域,可... 详细信息

总结了当前我国生态安全及预警相关概念,对比分析了现有生态安全预警思路与方法,以生产空间为研究对象,从产业发展导致的生态环境问题角度出发,研究提出了产业发展对生态安全影响预警的技术框架,建议针对资源消耗型、环境破坏型区域,可通过资源环境承载力评价,基于超载状况及其变化趋势进行预警;针对生态破坏型区域及具体产业,可通过生态系统承载力评价、生态阈值分析等方式进行预警分析。最后提出未来生态安全预警的重点研究方向,包括产业发展对生态安全的影响机制、产业胁迫因子生态阈值、基于人体健康的生态安全预警研究等。

关键词：产业发展生态安全预警

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武夷山主峰黄岗山片区生态安全格局构建研究

环境工程技术学报 2022年第5期12卷 1437-1445页

作者：朱振肖柴慧霞张箫王夏晖牟雪洁于洋生态环境部环境规划院

生态安全格局理论为区域尺度的景观综合体生态保护修复实践提供了理论依据和技术路径。以我国东南地区重要的生态屏障--武夷山主峰黄岗山片区为例,按照识别生态源地—构建阻力面—提取生态廊道的研究框架,采用定性与定量相结合的方法,... 详细信息

生态安全格局理论为区域尺度的景观综合体生态保护修复实践提供了理论依据和技术路径。以我国东南地区重要的生态屏障--武夷山主峰黄岗山片区为例,按照识别生态源地—构建阻力面—提取生态廊道的研究框架,采用定性与定量相结合的方法,评估提取区域内生态系统服务功能极重要区,将其与自然保护地叠加生成生态源地;采用地类和地形因子对研究区设置阻力面,运用最小累积阻力模型提取生态廊道,将生态功能重要区确定为生态缓冲区,构建黄岗山片区生态安全格局。结果显示:黄岗山片区生态源地面积为5808.80 km^(2),占区域面积的34.16%,占比较大,主要分布在江西省南部、福建省北部山地的交界地带;提取生态廊道共21条,长度为455.1 km,呈组团式将中部与东北部、西南部源地斑块连通起来;生态缓冲区面积为1574.13 km^(2),占比为9.2%,主要分布在研究区的北部山区。研究打破省域、市域、流域界限,将研究区视为一个完整的生命共同体,充分考虑生态结构的完整性、生态过程的连通性以及生态功能的重要性,构建区域尺度点线面状的生态安全格局,可为当地实施区域一体化保护和修复提供空间指引。

关键词：生态安全格局最小累积阻力模型生态系统服务生态保护修复黄岗山片区