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我国环境影响评价制度的演进、研究热点与“十五五”趋势前瞻
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作者 徐鹤 樊瑞娜 《环境影响评价》 2026年第1期1-12,共12页
环境影响评价(以下简称“环评”)作为我国一项重要的环境管理制度,自1979年《中华人民共和国环境保护法(试行)》首次提出并确立以来,已成为环境保护领域形成最早且付诸实施的法律制度之一。本文系统回顾了我国环评制度的发展历程;基于... 环境影响评价(以下简称“环评”)作为我国一项重要的环境管理制度,自1979年《中华人民共和国环境保护法(试行)》首次提出并确立以来,已成为环境保护领域形成最早且付诸实施的法律制度之一。本文系统回顾了我国环评制度的发展历程;基于文献计量方法,对1995—2025年我国环评领域的研究文献进行了系统分析,识别并总结了主要研究方向与学术热点;结合当前环评实践中面临的挑战,对我国环评制度在“十五五”期间的发展趋势作出前瞻性展望,并从制度耦合、新领域拓展、理论创新、技术赋能与体制完善等方面提出具体建议,以期为制度完善与政策优化提供参考。 展开更多
关键词 环境影响评价 发展历程 文献计量法 研究进展 学术热点 展望
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A photo-accelerated nanoplatform for image-guided synergistic chemo-photodynamic therapy
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作者 Di Zhang xu he +4 位作者 Xiaoying Kang xue Meng Ji Qi Zhifang Wu Ningbo Li 《Chinese Chemical Letters》 2025年第12期339-344,共6页
The efficient and safe strategy is highly desirable for effective tumor treatment,yet the development is still unsatisfied.In this work,we develop a photo-accelerated nanoplatform for image-guided synergistic chemo-ph... The efficient and safe strategy is highly desirable for effective tumor treatment,yet the development is still unsatisfied.In this work,we develop a photo-accelerated nanoplatform for image-guided synergistic chemo-photodynamic therapy.We first synthesize an aggregation-induced emission luminogen(AIEgen)with outstanding type-Ⅰ and type-Ⅱ photodynamic therapy(PDT)properties.By integrating the high-performance AIEgen with a hypoxia-responsive prodrug and camouflaging with M1 macrophage membrane,a tumor-targeting theranostic agent is created.Upon light trigger,the type-Ⅱ PDT process depletes oxygen in the tumor microenvironment,exacerbating hypoxia and promoting prodrug activation.Meanwhile,the type-Ⅰ PDT mechanism,being less reliant on oxygen,ensures that the overall PDT efficacy remains largely unaffected.Consequently,this light-triggered synergistic PDT-chemotherapy system demonstrates enhanced therapeutic performance.In vivo fluorescence imaging precisely delineates tumor sites,guiding subsequent treatment.The photo-triggered prodrug activation and PDT significantly boost the therapeutic outcomes of the tumor.This approach presents a compelling solution for targeted and efficient tumor treatment. 展开更多
关键词 Aggregation-induced emission Photodynamic therapy THERANOSTICS HYPOXIA Synergistic chemotherapy
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Image Stabilization Residuals Caused by Tip-tilt of Fast Steering Mirror in the China Space Station Telescope
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作者 Long Li Cheng-Hao Li +6 位作者 Quan Zhang Yuan-Peng Gao Zi-Huang Cao Zhi-Rui Cao xu he Li-Hao Zhang Wei Wang 《Research in Astronomy and Astrophysics》 2025年第4期209-217,共9页
The China Space Station Telescope(CSST)is a 2 m three-mirror anastigmat equipped with a Fast Steering Mirror(FSM),which is part of its precision image stabilization system.The FSM is used to compensate for residuals f... The China Space Station Telescope(CSST)is a 2 m three-mirror anastigmat equipped with a Fast Steering Mirror(FSM),which is part of its precision image stabilization system.The FSM is used to compensate for residuals from the previous stage of the image stabilization system.However,a new type of image stabilization residual caused by image rotation and projection distortion is introduced when the FSM performs tip-tilt adjustments,reducing both the image stabilization accuracy and the absolute pointing accuracy of the CSST.In this paper,we propose a scheme to compute the image stabilization residuals across the full field of view(FOV)by using a reference star as the target for stabilization control,which can be utilized for subsequent image position correction.To achieve this,we developed a linear optical model for image point displacement by simplifying an existing image point displacement model and incorporating more readily available parameters.The computational accuracy of the new model is equivalent to that of the original,with computational differences of less than 0.03μm.Based on this linear model,we established a calculation model for image stabilization residuals,including those due to image rotation and projection distortion caused by FSM tip-tilt adjustments.This model provides a theoretical foundation for quantifying such residuals during the image stabilization process.Finally,the results of testing using this scheme are provided.Experimental results demonstrate that within the observation FOV of the CSST,when the FSM tilts by(1″,1″),the maximum absolute value of the image stabilization residuals accounts for 20%of the total image stabilization accuracy requirement.This finding underscores the necessity of computing and correcting these residuals to meet performance requirements. 展开更多
关键词 telescopes techniques:image processing methods:analytical
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Triphenyl Phosphine Oxide and Carbazole-based Polymer Host Materials for Green Phosphorescent Organic Light-emitting Diodes
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作者 Hong-ji Jiang Qing-wei Zhang +2 位作者 xu he Xiao-lin Zhang Xin-wen Zhang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第5期611-622,共12页
Four novel polymers, poly(3,6-9-decyl-carbazole-alt-1,3-benzene) (PB13CZ), poly(3,6-9-decyl-carbazole-alt- bis(4-phenyl) (phenyl) phosphine oxide) (PTPPO38CZ), poly(3,6-9-decyl-carbazole-alt-2,4-phenyl(d... Four novel polymers, poly(3,6-9-decyl-carbazole-alt-1,3-benzene) (PB13CZ), poly(3,6-9-decyl-carbazole-alt- bis(4-phenyl) (phenyl) phosphine oxide) (PTPPO38CZ), poly(3,6-9-decyl-carbazole-alt-2,4-phenyl(diphenyl) phosphine oxide) (PTPPO13CZ) and poly(3,6-9-decyl-carbazole-alt-bis(3-phenyl) (phenyl) phosphine oxide) (PTTPO27CZ) were synthesized, and their thermal, photophysical properties and device applications were further investigated to correlate the chemical structures with the photoelectric performance of bipolar host materials for phosphorescent organic light emitting diodes. All of them show high thermal stability as revealed by their high glass transition temperatures and thermal decomposition temperatures at 5% weight loss. These polymers have wide band gaps and relatively high triplet energy levels. As a result, the spin coating method was used to prepare the green phosphorescent organic light emitting diodes with polymers PTPPO38CZ, PTPPO13CZ and PTTPO27CZ as the typical host materials. The green device of polymer PTPPO38CZ as host material shows electroluminescent performance with maximum current efficiency of 2.16 cd.A-1, maximum external quantum efficiency of 0.7%, maximum brightness of 1475 cd.m-2 and reduced efficiency roll-off of 7.14% at 600 cd.m-2, which are much better than those of the same devices hosted by polymers PTTPO27CZ and PTPPO13CZ. 展开更多
关键词 Triphenyl phosphine oxide Phosphorescent organic light-emitting diode Thermal stability Triplet energy levels Polymer host materials Electroluminescent performance
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PECVD制备类液纳米涂层及其表面抗结冰性能研究
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作者 周国伟 邹晖 +4 位作者 陈威 徐赫 范冬冬 刘文娜 叶羽敏 《表面技术》 北大核心 2026年第2期242-253,共12页
目的以等离子增强化学气相沉积(PECVD)方法制备类液纳米涂层并研究其在光滑与粗糙表面的疏液性能与抗结冰性能。方法采用PECVD技术,以环状硅氧烷(四甲基环四硅氧烷,TMCTS)和线性硅氧烷(六甲基二硅氧烷,HMDSO)为前驱体,分别制备表面光滑... 目的以等离子增强化学气相沉积(PECVD)方法制备类液纳米涂层并研究其在光滑与粗糙表面的疏液性能与抗结冰性能。方法采用PECVD技术,以环状硅氧烷(四甲基环四硅氧烷,TMCTS)和线性硅氧烷(六甲基二硅氧烷,HMDSO)为前驱体,分别制备表面光滑的等离子聚合HMDSO(H)涂层、表面粗糙的等离子聚合TMCTS(T)涂层和复合TMCTS/HMDSO(T/H)涂层。利用傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、原子力显微镜(AFM)和接触角测试仪对涂层的成分结构、形貌及润湿性进行表征。通过结冰延迟时间和冰黏附强度测试评估涂层的抗结冰性能。通过高温浸煮、酸碱腐蚀、紫外加速老化、膜基结合力和磨损测试评估涂层的耐久性。结果PECVD制备的复合T/H涂层展现出优于光滑H涂层和粗糙T涂层的疏液性和抗结冰性能。依靠纳米粗糙复合结构与低表面能特性协同作用,其静态水接触角达到151°,滑动角低至2°。在-15℃测试条件下,复合T/H涂层将水滴的结冰起始时间延迟至240 s(较未处理表面提升14倍),完全冻结时间延长至600 s(提升10倍)。同时,该涂层的冰黏附强度仅为23.4 kPa,较未处理表面(217.5 kPa)降低89%。在热稳定性、抗紫外性、耐溶剂性、膜基结合力和耐磨性测试中,复合T/H涂层均表现出色的稳定性。结论通过PECVD技术制备的复合T/H涂层具有优良的疏液与抗结冰性能,有望为电力系统关键设备如绝缘子等表面的防覆冰难题提供新的解决方案。 展开更多
关键词 抗结冰 类液涂层 超疏水表面 等离子增强化学气相沉积 纳米结构 绝缘子
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基于张量低秩学习的多视图子空间聚类方法
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作者 史德胜 徐鹤 李鹏 《数据采集与处理》 北大核心 2026年第1期215-230,共16页
多视图聚类是一种机器学习技术,通过整合多源信息可以显著提升聚类性能。然而,现有方法在处理多视图数据时未能充分利用张量低秩表示与亲和度矩阵之间的内在相关性,同时在应对数据缺失、噪声和异常值时表现不佳。为解决这些问题,提出了... 多视图聚类是一种机器学习技术,通过整合多源信息可以显著提升聚类性能。然而,现有方法在处理多视图数据时未能充分利用张量低秩表示与亲和度矩阵之间的内在相关性,同时在应对数据缺失、噪声和异常值时表现不佳。为解决这些问题,提出了一种基于张量低秩学习的多视图子空间聚类方法。该方法通过对数据样本施加低秩约束,深入挖掘数据点之间的高阶关联性,精确识别数据的子空间结构。同时,引入张量奇异值分解和加权张量核范数最小化方法,对亲和度矩阵进行优化,将聚类问题转化为一个凸优化问题求解,确保了模型的鲁棒性和效率。此外,所提方法在捕捉多视图数据复杂关联性方面表现出色,能够更准确地识别数据的潜在子空间结构。实验结果表明,所提方法在4类基准数据集上的性能优于现有方法,具有高的准确性和鲁棒性。 展开更多
关键词 多视图聚类 张量低秩 子空间聚类 高阶关联性 张量分解
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Effects of total saponins of Panax notoginseng on immature neuroblasts in the adult olfactory bulb following global cerebral ischemia/reperfusion 被引量:16
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作者 xu he Feng-jun Deng +3 位作者 Jin-wen Ge Xiao-xin Yan Ai-hua Pan Zhi-yuan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第9期1450-1456,共7页
The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volum... The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volume and promote proliferation and differentiation of neural stem cells in the hippocampus and lateral ventricles. However, there is a lack of studies on whether total saponins of Panax notoginsertg have potential benefits on immature neuroblasts in the olfactory bulb following ischemia and reperfusion. This study established a rat model of global cerebral ischemia and reperfusion using four-vessel occlusion. Rats were administered total sa- ponins of Panax notoginseng at 75 mg/kg intraperitoneally 30 minutes after ischemia then once a day, for either 7 or 14 days. Total saponins of Panax notoginseng enhanced the number of dou- blecortin (DCX)+ neural progenitor ceils and increased co-localization of DCX with neuronal nuclei and phosphorylated cAMP response element-binding/DCX+ neural progenitor cells in the olfactory bulb at 7 and 14 days post ischemia. These findings indicate that following global brain ischemia/reperfusion, total saponins of Panax notoginseng promote differentiation of DCX+ cells expressing immature neuroblasts in the olfactory bulb and the underlying mechanism is related to the activation of the signaling pathway of cyclic adenosine monophosphate response element binding protein. 展开更多
关键词 nerve regeneration total saponins of Panax notoginseng cerebral ischemia/reperfusion immature neurons NEUROGENESIS DOUBLECORTIN olfactory bulb neural regeneration
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文献阅读与讨论教学模式在医学免疫学中的探讨与实践
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作者 林玲辉 徐鹤 宋香全 《湖北开放职业学院学报》 2026年第1期172-174,共3页
医学免疫学是医学专业的核心基础课程,为提升医学免疫学教学质量,开阔学生视野,培养学生科研思维,满足新医科背景下对医学生提出新要求。本教学团队进行了基于TBL的文献阅读与讨论教学模式在医学免疫学教学过程中探索。通过有目的地精... 医学免疫学是医学专业的核心基础课程,为提升医学免疫学教学质量,开阔学生视野,培养学生科研思维,满足新医科背景下对医学生提出新要求。本教学团队进行了基于TBL的文献阅读与讨论教学模式在医学免疫学教学过程中探索。通过有目的地精选高质量的文献阅读,设计“课前准备—课中互动—课后拓展”三阶段教学流程,结合小组协作、汇报讨论及多维度评价机制,促进学生对课堂理论知识的理解与应用,提升学生的协作精神,培养学生的科研思维,激发学生的科研兴趣。采用问卷调查评估教学效果,结果表明,该教学模式能有效促进基础理论与科研热点的融合、知识内化与能力迁移,为新医科背景下医学免疫学教学改革提供了实践参考。 展开更多
关键词 文献阅读与讨论 医学免疫学 TBL模式 教学改革
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Degradation of tetracycline hydrochloride by ultrafine TiO_(2) nanoparticles modified g-C_(3)N_(4) heterojunction photocatalyst:Influencing factors,products and mechanism insight 被引量:7
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作者 Bin Zhang xu he +8 位作者 Chengze Yu Guocheng Liu Dong Ma Chunyue Cui Qinghua Yan Yingjie Zhang Guangshan Zhang Jun Ma Yanjun Xin 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第3期1337-1342,共6页
The unique heterojunction photocatalyst of graphite carbon nitride (g-C_(3)N_(4)) modified ultrafine TiO_(2) (g-C_(3)N_(4)/TiO_(2)) was successfully fabricated by electrochemical etching and co-annealing method. Howev... The unique heterojunction photocatalyst of graphite carbon nitride (g-C_(3)N_(4)) modified ultrafine TiO_(2) (g-C_(3)N_(4)/TiO_(2)) was successfully fabricated by electrochemical etching and co-annealing method. However, the effects of various environmental factors on the degradation of TC by g-C_(3)N_(4)/TiO_(2) and the internal reaction mechanism are still unclear. In this study, the effects of initial pH, anions, and cations on the photocatalytic degradation of tetracycline hydrochloride (TC) by g-C_(3)N_(4)/TiO_(2) were systematically explored, and the scavenging experiment and intermediate detection were conducted to better reveal the mechanism on photocatalytic degradation of TC. The results showed that the removal efficiency of photocatalytic degradation of TC by g-C_(3)N_(4)/TiO_(2) could reach 99.04% under Xenon lamp irradiation within 120 min. The unique g-C_(3)N_(4)/TiO_(2) heterojunction photocatalyst showed excellent photocatalytic performance for the degradation of TC at pH 3~7, and possesses outstanding anti-interference ability to NO_(3)^(-), Cl^(-), Na^(+), Ca^(2+) and Mg^(2+) ions in natural waters during the photocatalytic degradation TC process. Superoxide radicals (O_(2)^(·-)) and hydroxyl radicals (^(·)OH) were proved as the main reactive species for TC degradation, and the possible mechanism of the unique photocatalytic system for g-C_(3)N_(4)/TiO_(2) was also proposed. The above results can provide a reliable basis and theoretical guidance for the design and application of visible photocatalyst with high activity to degrade the actual wastewater containing TC. 展开更多
关键词 PHOTOCATALYTIC TiO_(2) G-C3N4 Tetracycline hydrochloride MECHANISM
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Influence of Li^(+)/Al^(3+) on the corrosion behavior of Li-Al layered double hydroxides(LDHs) film on LA51 magnesium alloys 被引量:4
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作者 Xinfang Zhang Ruihong Li +10 位作者 Xiaoyan Feng xue Pang xu he Zili Jin Huiping Ren Dashuang Wang Kailin Li Xingjian Dai Zhilan Du Quan Zhou Yuxin Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1083-1093,共11页
A hierarchical superhydrophobic Al-Li layered double hydroxide(LDH)films with different Li^(+)/Al^(3+)molar ratios of 1:1,1:2,2:1,p H value of 11.5 and reaction temperature of 125°C,have been fabricated on the su... A hierarchical superhydrophobic Al-Li layered double hydroxide(LDH)films with different Li^(+)/Al^(3+)molar ratios of 1:1,1:2,2:1,p H value of 11.5 and reaction temperature of 125°C,have been fabricated on the surface of Mg-5Li-1Al(LA51)alloys by hydrothermal method following the characteristics of controllable cation structure and exchangeable anion between layers.The properties of the films were investigated by X-ray diffractometer(XRD),scanning electron microscope(SEM)and energy dispersive spectrometer(EDS).XRD and SEM results indicate that the Al-Li LDH films are successfully prepared on LA51 alloys.The contact angle(CA)was measured to be about100.7°,indicating that the surface wettability of the film converted from hydrophilic to hydrophobic by surface modification.The corrosion resistance of Al-Li LDH films was evaluated by Tafel polarization curve and electrochemical impedance spectroscopy(EIS).Surprisingly,Tafel polarization curve and EIS test reveal that the Al-Li LDH films prepared at the molar ratio of Li^(+)/Al^(3+)1:2,p H 11.5 and temperature125°C have better corrosion resistance in 0.1 M Na Cl neutral solution.In addition,the formation mechanism and corrosion mechanism of the films on the surface of LA51 alloy are also proposed.It provides innovative synthetic materials and novel design ideas for the preparation of high-efficiency anti-corrosion coatings on LA51 alloys,whose application can be extended in industrial fields. 展开更多
关键词 Magnesium alloys Corrosion resistance Al-Li LDH SUPER-HYDROPHOBICITY
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Comparison of tumor response following conventional versus drug-eluting bead transarterial chemoembolization in early-and very early-stage hepatocellular carcinoma 被引量:6
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作者 Murtuza Razi Syed Safiullah +3 位作者 Jianping Gu xu he Mustafa Razi Jie Kong 《Journal of Interventional Medicine》 2022年第1期10-14,共5页
Objective:To compare the safety of conventional transarterial chemoembolization(cTACE)vs drug-eluting bead TACE(DEB-TACE)in very early-and early-stage hepatocellular carcinoma(HCC).Methods:Data of patients with early-... Objective:To compare the safety of conventional transarterial chemoembolization(cTACE)vs drug-eluting bead TACE(DEB-TACE)in very early-and early-stage hepatocellular carcinoma(HCC).Methods:Data of patients with early-and very early-stage HCC treated with cTACE or DEB-TACE were evaluated retrospectively in this study.A total of 40 patients were included,20 treated with cTACE and 20 with DEB-TACE.The cTACE and DEB-TACE groups were comprised of 80%and 75%males,while there were 20%females in cTACE group and 25%in Deb-TACE group respectively.The mean age of patients in cTACE group was 57.43+5.6 years,while it was 56.4+5.5 years in DEB-TACE group.All patients had liver status of Child–Pugh Class A and a score≤7 in Child-Pugh class type B in very early-(stage 0)or early-phase(stage A)stages according to the Barcelona Clinic Liver Cancer(BCLC)system.Results:The Child-Pugh class degradation in the cTACE group was slightly higher than that in the DEB-TACE group.Serious complications like peritumoral parenchymal ischemia were observed in 4 patients in the cTACE group and 5 in the DEB-TACE group.Localized bile duct dilation was seen in 2 patients in the cTACE group and 6 in the DEB-TACE group.No significant variation in serious complications between the two groups was established in localized bile duct dilatation.Other minor complications noted were liver failure,liver abscess,liver infarction,acute cholecystitis,biliary tree necrosis,and mortality.Further,no substantial variation in tumor response between the groups was reported immediately and 1-year post-procedural assessment.Conversion rate to other treatment modalities such as surgical resection,radiofrequency ablation(RFA),or swap between cTACE and DEB-TACE was substantially higher in the DEB-TACE group(40%)than in the cTACE group(10%)at the 1-year completion period of the study.Conclusion:In terms of tumor response,the DEB-TACE group showed a better response,to some extent,as an initial therapy for HCC in the early stages as compared to the cTACE group,and DEB-TACE also exhibited better clinical efficacy in patients with HCC. 展开更多
关键词 HCC TACE cTACE DEB-TACE
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The mechanism of hydraulic fracturing assisted oil displacement to enhance oil recovery in low and medium permeability reservoirs 被引量:3
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作者 LIU Yikun WANG Fengjiao +8 位作者 WANG Yumei LI Binhui ZHANG Dong YANG Guang ZHI Jiqiang SUN Shuo WANG xu DENG Qingjun xu he 《Petroleum Exploration and Development》 CSCD 2022年第4期864-873,共10页
Aiming at the technology of hydraulic fracturing assisted oil displacement which combines hydraulic fracturing,seepage and oil displacement,an experimental system of energy storage and flowback in fracturing assisted ... Aiming at the technology of hydraulic fracturing assisted oil displacement which combines hydraulic fracturing,seepage and oil displacement,an experimental system of energy storage and flowback in fracturing assisted oil displacement process has been developed and used to simulate the mechanism of percolation,energy storage,oil displacement and flowback of chemical agents in the whole process.The research shows that in hydraulic fracturing assisted oil displacement,the chemical agent could be directly pushed to the deeper area of the low and medium permeability reservoirs,avoiding the viscosity loss and adhesion retention of chemical agents near the pay zone;in addition,this technology could effectively enlarge the swept volume,improve the oil displacement efficiency,replenish formation energy,gather and exploit the scattered residual oil.For the reservoir with higher permeability,this measure takes effect fast,so to lower cost,and the high pressure hydraulic fracturing assisted oil displacement could be adopted directly.For the reservoir with lower permeability which is difficult to absorb water,hydraulic fracturing assisted oil displacement with surfactant should be adopted to reduce flow resistance of the reservoir and improve the water absorption capacity and development effect of the reservoir.The degree of formation energy deficit was the main factor affecting the effective swept range of chemical agents.Moreover,the larger the formation energy deficit was,the further the seepage distance of chemical agents was,accordingly,the larger the effective swept volume was,and the greater the increase of oil recovery was.Formation energy enhancement was the most important contribution to enhanced oil recovery(EOR),which was the key to EOR by the technology of hydraulic fracturing assisted oil displacement. 展开更多
关键词 hydraulic fracturing chemical flooding formation energy enhancement remaining oil distribution oil displacement mechanism enhancing oil recovery
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A Multi-Stage Green Barrier Strategy for the Control of Global SARS-CoV-2 Transmission via Cold Chain Goods 被引量:4
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作者 xu he Xinwang Liu +6 位作者 Pan Li Panpan Wang Haijun Cheng Wenqian Li Boda Li Ting Liu Jun Ma 《Engineering》 SCIE EI 2022年第2期13-16,共4页
1.The object-to-human transmission route of SARS-CoV-2 At the time of writing,coronavirus disease 2019(COVID-19),which is caused by the severe acute respiratory syndrome coron-avirus 2(SARS-CoV-2),has been a global pa... 1.The object-to-human transmission route of SARS-CoV-2 At the time of writing,coronavirus disease 2019(COVID-19),which is caused by the severe acute respiratory syndrome coron-avirus 2(SARS-CoV-2),has been a global pandemic for more than a year.As of 22 September 2021,the global cumulative incidence exceeds 229 million cases,and the number of deaths has exceeded 4.75 million[1].The current situation of epidemic prevention and control within the countries around the world can be roughly divided into two stages:the pandemic stage that the United States,the United Kingdom,and India are still experiencing(as of 23 September 2021,newly reported cases in the last 24 h in the United States,United Kingdom,and India are 202840,31095,and 26964,respectively[1]);and the normalized epidemic pre-vention and control stage that countries such as China and New Zealand are currently in. 展开更多
关键词 PREVENTION STRATEGY CHAIN
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Macular changes of neuromyelitis optica through spectral-domain optical coherence tomography 被引量:3
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作者 Lu Cheng Jing Wang +2 位作者 xu he xun xu Zhen-Fen Ling 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第11期1638-1645,共8页
AIM: To evaluate the thickness of the retinal layers in the macula using spectral-domain optical coherence tomography(SD-OCT) in patients with neuromyelitis optica(NMO). METHODS: Spectralis SD-OCT, utilizing aut... AIM: To evaluate the thickness of the retinal layers in the macula using spectral-domain optical coherence tomography(SD-OCT) in patients with neuromyelitis optica(NMO). METHODS: Spectralis SD-OCT, utilizing automated macular layer segmentation, was performed in 26 NMO patients and 26 healthy controls. Visual function including visual field tests and pattern visual evoked potential were recorded in study subjects.RESULTS: Forty-one eyes from 26 NMO patients and52 eyes from 26 age- and sex-matched healthy controls were included. Besides total macular volume, peri-paipillary retinal nerve fiber layer(RNFL) thickness, the thickness of macular RNFL, ganglion cell layer(GCL) and inner plexiform layer(IPL) were also significantly reduced in NMO patients compared to those inhealthy controls(P 〈0.000). No differences were found in the thickness of macular inner nuclear layer(INL), outer plexiform layer(OPL), and outer nuclear layer(ONL) between the two groups. Reversely, the outer retinal layer(ORL) was shown to be thicker in NMO than controls(P 〈0.05).Compared with the peri-papillary RNFL thickness, the GCL thickness was demonstrated to correlate with visual function better.CONCLUSION: The study provides in vivo evidence of retinal neural loss in NMO patients and demonstrates abetter structure-function correlation between retinal ganglion cell and visual function than peri-papillary RNFL does. In addition, no evidence of primary neural damage is found. Besides, the photoreceptor cells and retinal pigments epithelial(RPE) cells presumably proliferated in compensation in NMO after retinal neural loss. 展开更多
关键词 neuromyelitis optica optical coherencetomography macular layer thickness ganglion cell loss
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Reshapeable,rehealable and recyclable sensor fabricated by direct ink writing of conductive composites based on covalent adaptable network polymers 被引量:2
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作者 xu he Yuchen Lin +6 位作者 Yuchen Ding Arif M Abdullah Zepeng Lei Yubo Han Xiaojuan Shi Wei Zhang Kai Yu 《International Journal of Extreme Manufacturing》 SCIE EI 2022年第1期94-107,共14页
Covalent adaptable network(CAN)polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable,rehealable,and fully recyclable electronics.On the other hand,3D printing as a deterministic man... Covalent adaptable network(CAN)polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable,rehealable,and fully recyclable electronics.On the other hand,3D printing as a deterministic manufacturing method has a significant potential to fabricate electronics with low cost and high design freedom.In this paper,we incorporate a conductive composite consisting of polyimine CAN and multi-wall carbon nanotubes into direct-ink-writing 3D printing to create polymeric sensors with outstanding reshaping,repairing,and recycling capabilities.The developed printable ink exhibits good printability,conductivity,and recyclability.The conductivity of printed polyimine composites is investigated at different temperatures and deformation strain levels.Their shape-reforming and Joule heating-induced interfacial welding effects are demonstrated and characterized.Finally,a temperature sensor is 3D printed with defined patterns of conductive pathways,which can be easily mounted onto 3D surfaces,repaired after damage,and recycled using solvents.The sensing capability of printed sensors is maintained after the repairing and recycling.Overall,the 3D printed reshapeable,rehealable,and recyclable sensors possess complex geometry and extend service life,which assist in the development of polymer-based electronics toward broad and sustainable applications. 展开更多
关键词 bond exchange reactions polyimine covalent adaptable networks direct ink writing rehealable electronics RECYCLABILITY
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Activity Pattern and Habitat Use of Shorebirds in an Artificial Wetland Complex:A Case Study of Breeding Pied Avocet in the Yellow River Delta,China 被引量:1
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作者 LI Dong LI Bin +4 位作者 xu he FAN Chao WU Yang ZHANG Yuxin HOU Xiyong 《Chinese Geographical Science》 SCIE CSCD 2024年第4期618-630,共13页
With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important ro... With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird population.Satellite tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their habitats.In this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),China.The results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),respectively.This species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding ground.The distance between breeding ground and feeding ground was less than 6 km.It is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird conservation.This research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones. 展开更多
关键词 satellite tracking home range habitat use artificial wetland coastal zone Pied Avocet Yellow River Delta China
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Effects of Diet on the Volatile Flavor and Nutritional Ingredients of Common Octopus(Octopus vulgaris) 被引量:1
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作者 LUO Qihao WANG Weijun +5 位作者 LI Zan ZHU Xinghua WANG xue ZHANG Tonghua xu he YANG Jianmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期393-401,共9页
Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South Chin... Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients. 展开更多
关键词 Octopus vulgaris volatile flavor substances fatty acids amino acids diet effect
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Deformation and failure behavior of heterogeneous Mg/SiC nanocomposite under compression 被引量:1
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作者 Xi Luo Jinling Liu +3 位作者 Leigang Zhang xu he Ke Zhao Linan An 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第12期3433-3446,共14页
The heterogeneous magnesium(Mg) matrix nanocomposite with dispersed soft phase exhibits high strength and toughness. Herein, the deformation behavior and failure process were investigated to reveal the unique mechanic... The heterogeneous magnesium(Mg) matrix nanocomposite with dispersed soft phase exhibits high strength and toughness. Herein, the deformation behavior and failure process were investigated to reveal the unique mechanical behavior of the heterogeneous microstructure under compression. The extensive plastic deformation is accompanied by the flattening and tilting of the soft phase, inhibiting strain localization and leading to strain hardening. Moreover, a stable crack multiplication process is activated, which endows high damage tolerance to the heterogeneous Mg matrix nanocomposites. The final failure of the composite is caused by crack coalescence in the shear plane along a tortuous path. The presence of dispersed soft phases within the hard matrix induces a noticeable change in mechanical response. Especially,the malleability of the heterogeneous Mg matrix nanocomposite is two and ten times higher than that of pure Mg and the homogeneous Mg matrix nanocomposite, respectively. The current study provides a novel strategy to break the trade-off between strength and toughness in metal matrix nanocomposites. 展开更多
关键词 Magnesium matrix nanocomposites Heterogeneous structure MALLEABILITY Microstructural evolution
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Solitary plasmacytoma of the left rib misdiagnosed as angina pectoris:A case report 被引量:1
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作者 Jian Yao xu he +4 位作者 Cheng-Yuan Wang Li Hao Li-Li Tan Chun-Jian Shen Ming-Xiao Hou 《World Journal of Clinical Cases》 SCIE 2022年第20期7037-7044,共8页
BACKGROUND Solitary plasmacytoma in the left rib is rare and can cause chest discomfort such as chest pain and tightness,and its clinical manifestations are not typical,so it is often misdiagnosed.We report a case of ... BACKGROUND Solitary plasmacytoma in the left rib is rare and can cause chest discomfort such as chest pain and tightness,and its clinical manifestations are not typical,so it is often misdiagnosed.We report a case of left costal plasmacytoma misdiagnosed as angina pectoris.We also review the literature and provide suggestions as to how to avoid misdiagnosis.CASE SUMMARY A 77-year-old man with a history of intermittent chest tightness for 3 years presented with pain in the left chest for 1 wk and was admitted to hospital.The cardiologists initially diagnosed angina pectoris but the findings of coronary angiography were not consistent with the symptoms.Computed tomography showed that the left eighth rib mass was accompanied by bone destruction.The patient was transferred to our department for further treatment.Preoperative biopsy indicated that the lesion was possibly malignant,and elective surgery was performed to remove the lesion.The size of the tumor was about 4 cm.The tumor was spindle-shaped and protruded into the pleural cavity,without invading the lungs.Postoperative pathology confirmed that the left rib lesion was plasmacytoma.After 14 mo follow-up,the patient died of systemic metastasis.CONCLUSION Left rib solitary plasmacytoma is a rare disease confined to a specific rib and can cause local pain.Attention should be paid to the differential diagnosis of angina pectoris to avoid misdiagnosis. 展开更多
关键词 Solitary plasmacytoma RIB MISDIAGNOSIS Angina pectoris Case report
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Venous thromboembolism in patients with COVID-19.A prevalent and a preventable complication of the pandemic 被引量:1
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作者 Murtuza Razi JianPing Gu +2 位作者 xu he Jie Kong Mohammed Jameeluddin Ahmed 《Journal of Interventional Medicine》 2021年第2期62-65,共4页
Coronavirus disease 2019 or most commonly known as COVID-19 is a trending global infectious disease which a few months ago was affirmed as a global health emergency or a pandemic by the WHO Emergency Committee.The com... Coronavirus disease 2019 or most commonly known as COVID-19 is a trending global infectious disease which a few months ago was affirmed as a global health emergency or a pandemic by the WHO Emergency Committee.The common symptoms manifested in this pandemic disease are high grade fever,cough,fatigue,shortness of breath and flu like symptom which can evolve into severe respiratory disorders such as pneumonia,acute respiratory distress syndrome(ARDS)and/or end-organ failure.Factors that contribute to the severity or high mortality rate in COVID-19 include old age,comorbidities like hypertension,diabetes,hyperlipidaemia,neutrophilia,and organ and coagulation dysfunction.Disseminated intravascular coagulation and other various coagulopathies including Venous thromboembolism have known to become a major contributing factor to high mortality rate.Venous thromboembolism is a disease which is a combination of deep vein thrombosis and pulmonary embolism.Prophylactic anticoagulation in patients prone to or with a pre-existing history of venous thromboembolism is associated with decreased mortality in severe COVID-19 pneumonia.This review article focuses upon COVID-19 and increased incidence of venous thromboembolism in patients infected by COVID-19 along with the role it has in high mortality rate in COVID-19 patients. 展开更多
关键词 Venous thromboembolism COVID-19 Coagulopathies Prophylactic anticoagulation PANDEMIC
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