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激光农业研究进展和展望
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作者 于合龙 周雷进雨 +4 位作者 徐兴梅 杨明来 jian zhang 姜京池 李卓识 《智能化农业装备学报(中英文)》 2024年第3期1-13,共13页
激光作为一种新兴的人造光源,是20世纪以来最伟大的发明之一,具有功率密度高、方向性好和优良的单色性等优点,在农业领域得到了广泛的应用。激光技术在植物生产、动物管理和菌物研究方面展现了显著优势。文章主要对激光技术在农业领域... 激光作为一种新兴的人造光源,是20世纪以来最伟大的发明之一,具有功率密度高、方向性好和优良的单色性等优点,在农业领域得到了广泛的应用。激光技术在植物生产、动物管理和菌物研究方面展现了显著优势。文章主要对激光技术在农业领域的研究进展和发展动态进行深入剖析。在植物生产方面,介绍了激光技术在植物诱变育种、促进植物生长发育、提高产量和品质、植物保护、植物检测和植物表型中的应用情况。在动物管理方面,主要分析了激光技术在动物遗传育种、动物生长、动物医疗和动物产品检测方面的研究。在菌物研究方面,重点总结激光技术在菌物育种、菌物生长发育及菌物检测和鉴定中的应用详情。最后,针对激光技术与农业生产研究相结合所面临的困难和挑战,从提升激光技术在农业生产管理中的精度和扩展其适用范围角度出发,提出了激光技术在植物生产精准化、动物生产管理优化和菌物生产科学化的发展方向。虽然激光技术在农业领域已经取得了一系列的成果,但在未来的研究中,应探索更多创新应用,并与人工智能和大数据技术相结合,进一步推进激光技术与农业产业的深度融合,以实现更高效、更智能的农业生产管理模式,为现代农业的发展带来更多机遇和突破。 展开更多
关键词 激光技术 农业生产 植物 动物 菌物
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紫甘蓝色素稳定性研究
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作者 付世涛 张剑鸣 +4 位作者 曹灿灿 汪志慧 秦超然 张建 熊辉 《大学化学》 CAS 2024年第4期367-372,共6页
本文以紫甘蓝蔬菜为原料,进行了pH、金属离子和各种食品添加剂等一系列稳定性分析,探索紫甘蓝色素的最佳存储和使用环境。研究表明,紫甘蓝色素对pH敏感,随着pH增大,色素保留率逐渐减小;不同金属离子对紫甘蓝色素的稳定性也有影响,Fe^(3+... 本文以紫甘蓝蔬菜为原料,进行了pH、金属离子和各种食品添加剂等一系列稳定性分析,探索紫甘蓝色素的最佳存储和使用环境。研究表明,紫甘蓝色素对pH敏感,随着pH增大,色素保留率逐渐减小;不同金属离子对紫甘蓝色素的稳定性也有影响,Fe^(3+)会破坏紫甘蓝色素的结构,降低稳定性,保留率仅为8.68%;而Ca^(2+)能提高其稳定性。添加剂蔗糖也可提高其稳定性,其中20 g∙L^(−1)的蔗糖水溶液可将保留率提升至119.48%;而食盐、苯甲酸钠和山梨酸钾均会降低其稳定性。 展开更多
关键词 紫甘蓝色素 影响因素 稳定性
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超高速激光金属沉积增材制造K648高温合金的显微组织与性能
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作者 王开明 刘炜 +7 位作者 都东 常保华 刘冠 胡永乐 仝永刚 张明军 张健 鞠江 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第7期2192-2203,共12页
采用一种新型的超高速激光金属沉积工艺以提高高铬高温合金的制造效率。分别使用透射电子显微镜、拉伸试验机、磨损试验机和电化学工作站对超高速激光金属沉积高铬K648高温合金的析出相生长行为、高温力学性能、耐磨性和耐腐蚀性进行研... 采用一种新型的超高速激光金属沉积工艺以提高高铬高温合金的制造效率。分别使用透射电子显微镜、拉伸试验机、磨损试验机和电化学工作站对超高速激光金属沉积高铬K648高温合金的析出相生长行为、高温力学性能、耐磨性和耐腐蚀性进行研究,并与传统激光金属沉积工艺进行比较。结果表明,超高速激光金属沉积K648合金的析出相尺寸明显小于传统激光金属沉积工艺制备的K648合金,700℃下的高温强度更高,且具有良好的耐磨性和耐腐蚀性。总之,超高速激光金属沉积制造的K648高铬高温合金具有良好的综合性能。 展开更多
关键词 增材制造 超高速激光金属沉积 K648高温合金 显微组织演变 性能
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光热协同驱动SrTiO_(x)负载CuCo催化CO_(2)-CH_(4)和H_(2)O共转化制备C_(2)含氧化合物
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作者 朱彦儒 张志军 +7 位作者 张健 蒋双江 安哲 宋红艳 舒心 习卫 郑黎荣 何静 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期164-178,共15页
催化转化CO_(2)为乙醇、乙醛等高值C_(2)含氧化合物是一个具有科学意义和经济价值的化学过程.然而,由于碳氧键活化难、多电子(≥10)转移过程复杂以及C–C偶联动力学缓慢等问题,导致该过程的反应效率低.CO_(2)因热力学稳定、动力学惰性,... 催化转化CO_(2)为乙醇、乙醛等高值C_(2)含氧化合物是一个具有科学意义和经济价值的化学过程.然而,由于碳氧键活化难、多电子(≥10)转移过程复杂以及C–C偶联动力学缓慢等问题,导致该过程的反应效率低.CO_(2)因热力学稳定、动力学惰性,其加氢活化通常是强吸热过程(如CO_(2)活化成CO的ΔH_(2)98K=42.1 kJ mol^(–1)),因此需要在一定温度下才能获得满意的CO_(2)转化率.与此同时,CH_(4)作为碳化学价态最低的化合物,其氧化过程与CO_(2)的还原过程可以耦合,共同转化为高值化学品,同样受到了广泛关注.但CH_(4)的活化同样需要高温等苛刻条件,因此,在温和条件下共转化CO_(2)和CH_(4),选择性构建高值C_(2)含氧化合物,是一个重要且具有挑战性的研究方向.本文提出利用光外场和水活化策略,即利用光解水产生的活性氢和活性氧物种,在温和条件下实现CO_(2)和CH_(4)的高效、高选择性活化及共转化.光照下,在钛酸锶(SrTiO_(x))负载的具有丰富Cu-Co界面的催化剂上,光解水产生的活性氢和活性氧物种,分别活化CO_(2)的碳氧键和CH_(4)的碳氢键,在Cu和Co位点上分别形成*CH_(x)O和*CH_(3)物种,进而通过C–C偶联高效生成C_(2)含氧化合物.在200°C和光照条件下,C_(2)含氧化合物(CH_(3)CHO和CH_(3)CH_(2)OH)的生成速率高达2.05 mmol g^(–1)h^(–1),同时产物选择性>86%.同位素标记、红外光谱示踪的原位反应和催化实验结果表明,紫外光激发下,SrTiO_(x)上的金属位点促进了光催化水裂解,生成活性氢和活性氧物种(该过程为整个反应的决速步骤).活性氢物种使吸附在SrTiO_(x)上的CO_(2)活化并转化为CO;随后,在CuI/Cu^(0)对上,CO加氢生成*CH_(x)O中间体.另一方面,在Co位点上,CH_(4)与活性氧物种发生反应,被活化为*CH_(3)中间体.最后,*CH_(x)O与*CH_(3)两种中间体在CuCo界面处发生C–C偶联反应,进而形成C_(2)含氧化合物.与传统的热催化下的CO_(2)和CH_(4)共转化过程相比,光热协同策略使该反应温度降低了超过600°C,并且反应活化能降低了约12 kJ mol^(–1),表明光热协同策略不仅可以大幅降低反应温度,还能极大提升反应动力学,为强吸热反应过程提供了一条提效降耗的反应途径.综上所述,本工作通过构建结构精准可控的SrTiO_(x)负载的CuCo邻近界面结构,同时利用光解水产生的活性氢/氧物种促进CO_(2)和CH_(4)活化,实现了高效定向共转化.本文提出的“光热协同”策略为高效活化CO_(2)制高值化学品提供了新的研究思路,同时显著降低了能耗,对解决强吸热催化反应高能耗问题提供了参考. 展开更多
关键词 光热协同 CO_(2)和CH_(4)共转化 SrTiO_(x)负载CuCo 水裂解 C_(2)含氧化合物
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利用光驱动的生物杂合系统实现CO_(2)转化生产化学品
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作者 干雅梅 柴甜甜 +5 位作者 张健 高聪 宋伟 吴静 刘立明 陈修来 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期294-303,共10页
太阳能作为清洁能源之一,为缓解化石燃料枯竭和温室气体排放等问题提供了一种高效、经济、可持续的解决方案.自然界中的植物和光合微生物通过自身的光合系统收集并转化太阳能,从而生产生物燃料和生物化学品.然而,由于自然光合系统存在... 太阳能作为清洁能源之一,为缓解化石燃料枯竭和温室气体排放等问题提供了一种高效、经济、可持续的解决方案.自然界中的植物和光合微生物通过自身的光合系统收集并转化太阳能,从而生产生物燃料和生物化学品.然而,由于自然光合系统存在光吸收范围相对较窄、光生电子在传输过程中易损耗等问题,限制了太阳能到化学品的转化效率.为了解决上述难题,科研人员模仿自然光合作用中的关键部分,探索构建人工光合系统,相关研究引起了广泛关注.本文通过将碲化镉量子点(CdTe QDs)与大肠杆菌(E.coli)相耦合,构建了一种光驱动无机-生物杂合系统(IBPHS),用于捕获太阳能并驱动CO_(2)转化合成高价值化学品.该系统主要由光催化模块和生物催化模块组成.在光催化模块中,通过生物合成CdTe QDs进行光能捕获,并将其转化为电子.通过敲除E.coli的Cd2+外排蛋白(ZNTA)编码基因,实现了E.coli胞内Cd2+过量积累.通过“时空耦合”方式,并借助共聚焦显微镜、高分辨率透射电镜和X射线能谱分析,确认了CdTe QDs在E.coli胞内的组装合成.利用紫外-可见分光光度计研究了光催化模块对光子的吸收能力.结果表明,光催化模块的吸收峰位于400-420 nm.利用瞬时光电流,评估了光催化模块的光生电子能力.实验发现,该模块可以产生0.07μA光电流,表明完成了光催化模块的构建.在生物催化模块中,将光催化模块产生的电子用于还原NAD+再生NADH.采用NADH生物传感器,分析了E.coli胞内NADH含量,结果表明,在蓝光照射下E.coli胞内NADH含量比黑暗条件下提高了5.1倍.在此基础上,通过表达NADH依赖型乳酸脱氢酶(LDH)将丙酮酸还原为乳酸,在蓝光光照下乳酸积累量达到了0.44 g/L,而黑暗条件下无乳酸积累,从而验证了生物催化模块的有效性.基于光催化模块和生物催化模块,进一步组装构建了IBPSH,用于驱动CO_(2)还原合成甲酸和丙酮酸.在蓝光照射下,IBPHS能够合成0.65 g/L甲酸和0.18 g/L丙酮酸,其CO_(2)利用速率分别达到51.98 mg/gDCW/h和21.92 mg/gDCW/h,超过了光合细菌.综上所述,本文利用光催化模块与生物催化模块相耦合的方式,组装构建了一种新型的人工光合系统,实现了光驱动CO_(2)还原合成高附加值化学品,为理性设计材料-生物杂合系统提供了借鉴,同时也为挖掘绿色生物制造潜力、开发太阳能化学制造平台提供参考. 展开更多
关键词 人工光合系统 CO_(2)利用 光能转换 CdTe生物合成 NADH再生
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Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications 被引量:1
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作者 Xin Yu Congcong Li +3 位作者 jian zhang Lili Zhao Jinbo Pang Longhua Ding 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期231-244,共14页
Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence states.It has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable attention.This comprehensive review is aimed at provi... Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence states.It has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable attention.This comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic nanomaterials.The fundamental con-cepts and principles of Sn_(3)O_(4)are introduced.Sn_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic reactions.Subsequently,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are discussed.Morphology control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)materials.The effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)nanomaterials.Furthermore,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic sensors.The discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and functionalities.Finally,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based nanomaterials.Through the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications. 展开更多
关键词 PHOTOCATALYSIS Sn_(3)O_(4)nanomaterials building heterostructures antibacterial therapy water splitting
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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation 被引量:1
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作者 Hang Gao jian zhang +4 位作者 Li Liu Lijun Fu Yan Zhao Germán Mazza Xin zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2317-2326,共10页
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw... Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation. 展开更多
关键词 Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution
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Using choroidal thickness to detect myopic macular degeneration 被引量:1
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作者 Ran Liu Meng Xuan +10 位作者 De-Cai Wang Ou Xiao Xin-Xing Guo jian zhang Wei Wang Monica Jong Padmaja Sankaridurg Kyoko Ohno-Matsui Qiu-Xia Yin Ming-Guang He Zhi-Xi Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期317-323,共7页
AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral hi... AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE. 展开更多
关键词 high myopia choroidal thickness myopic macular degeneration swept-source optical coherence tomography
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Insights into spinal muscular atrophy from molecular biomarkers
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作者 Xiaodong Xing Xinzhu Liu +6 位作者 Xiandeng Li Mi Li Xian Wu Xiaohui Huang Ajing Xu Yan Liu jian zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1849-1863,共15页
Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomar... Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness.It is one of the most common genetic causes of mortality among infants aged less than 2 years.Biomarker research is currently receiving more attention,and new candidate biomarkers are constantly being discovered.This review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and cons.We also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific biomarkers.This review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future research.Furthermore,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy. 展开更多
关键词 biomarkers disease progression gene-targeting therapy NEUROFILAMENTS Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes
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Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO_(2)into glycerol carbonate
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作者 Xufang Chen Xin Shu +5 位作者 Yanru Zhu jian zhang Zhigang Chai Hongyan Song Zhe An Jing He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期153-163,共11页
Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The dire... Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The direct carbonylation from glycerol with CO_(2)is considered a promising route,but still tough work due to the thermodynamic stability and the kinetic inertness of CO_(2).In this work,highlyselective direct carbonylation of glycerol and CO_(2)into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides(MgInCe-MMO),which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides(MgInCe-LDHs).By precisely modulating the surface basic-acidic properties and the oxygen vacancies,an efficient carbonylation of glycerol with CO_(2)has been achieved with a selectivity of up to>99%to glycerol carbonate.Deep investigation into the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified. 展开更多
关键词 Catalytic reaction engineering Glycerol carbonate Direct carbonylation from glycerol Carbon dioxide Mixed metal oxides Synergistic catalysis
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Butterfly taxonomic and functional diversity in the urban green spaces of Hefei city
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作者 Haicong Zeng Yan Zhu +5 位作者 Junyao zhang Chenliang Li jian zhang Hui Liu jianan Wang Dexian Zhao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期47-62,共16页
Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study a... Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study aimed to investigate the community composition characteristics of butterflies in urban green spaces within the context of rapid urbanization. Simultaneously, it explored the status and differences in butterfly taxonomic diversity, functional diversity, and functional traits among different types of urban green spaces, regions, and urban gradients to provide relevant insights for further improving urban green space quality and promoting biodiversity conservation. We conducted a year-long survey of 80 green spaces across different urban regions and ring roads within Hefei City, Anhui Province, with monthly sampling intervals over 187 transects. A total of 4822 butterflies, belonging to 5 families, 17 subfamilies, 40 genera, and 55 species were identified. The species richness, Shannon, Simpson, functional richness, and Rao's quadratic entropy indices of butterflies in urban park green spaces were all significantly higher than those in residential and street green spaces(P < 0.05). Differences in butterfly diversity and functional traits among different urban regions and ring roads were relatively minor, and small-sized, multivoltine, and long flying duration butterflies dominated urban green spaces. Overall, these spaces offer more favorable habitats for butterflies. However, some residential green spaces and street green spaces demonstrate potential for butterfly conservation. 展开更多
关键词 Urban green space planning Rapid urbanization Butterfly functional traits Green space types Urban biodiversity
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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope
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作者 Wei He Si-yuan Feng +4 位作者 jian zhang Hong-wu Tang Yang Xiao Sheng Chen Chun-sheng Liu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期197-208,共12页
Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawa... Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains. 展开更多
关键词 Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OPENFOAM
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Heterointerface engineering of rhombic Rh nanosheets confined on MXene for efficient methanol oxidation
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作者 Qi zhang Quanguo jiang +6 位作者 Xiang Yang Chi zhang jian zhang Lu Yang Haiyan He Guobing Ying Huajie Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期419-428,I0011,共11页
Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely li... Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely limits the overall electrocatalytic performance due to their insufficient cooperative effects.Herein,we report a controllable and robust heterointerface engineering strategy for the bottom-up fabrication of rhombic Rh nanosheets in situ confined on Ti_3C_(2)T_x MXene nanolamellas(Rh NS/MXene)via a convenient stereoassembly process.This unique design concept gives the resulting 2D/2D Rh NS/MXene heterostructure intriguing textural features,including large accessible surface areas,strong"face-toface"interfacial interactions,homogeneous Rh nanosheet distribution,ameliorative electronic structure,and high electronic conductivity.As a consequence,the as-prepared Rh NS/MXene nanoarchitectures exhibit exceptional electrocatalytic methanol oxidation properties in terms of a large electrochemically active surface area of 126.2 m~2 g_(Rh)~(-1),a high mass activity of 1056.9 mA mg_(Rh)-~1,and a long service life,which significantly outperform those of conventional particle-shaped Rh catalysts supported by carbon black,carbon nanotubes,reduced graphene oxide,and MXene matrixes as well as the commercial Pt nanoparticle/carbon black and Pd nanoparticle/carbon black catalysts with the same noble metal loading amount.Density functional theory calculations further demonstrate that the direct electronic interaction at the well-contacted 2D/2D heterointerfaces effectively enhances the adsorption energy of Rh nanosheets and induces a left shift of the d-band center,thereby making the Rh NS/MXene configuration suffer less from CO poisoning.This work highlights the importance of rational heterointerface design in the construction of advanced noble metal/MXene electrocatalysts,which may provide new avenues for developing the next-generation DMFC devices. 展开更多
关键词 Rhodium nanosheet Ti_(3)C_(2)T_(x)MXene HETEROINTERFACE ELECTROCATALYST Fuel cell
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Uncovering the electrooxidation behavior of 5-hydroxymethylfurfural on Ni/Co electrodes
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作者 Shilin Fan Bin Zhu +5 位作者 Xiao Yu Yang Gao Weiping Xie Yong Yang jian zhang Chunlin Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期1-7,共7页
Biomass,derived from plant photosynthesis that captures carbon dioxide to form carbohydrates,offers vast renewable reserves.The electrooxidation of biomass,coupled with the hydrogen evolution reaction,enables the simu... Biomass,derived from plant photosynthesis that captures carbon dioxide to form carbohydrates,offers vast renewable reserves.The electrooxidation of biomass,coupled with the hydrogen evolution reaction,enables the simultaneous production of biomass-based plastic monomers and green hydrogen,attracting significant scholarly interest.However,ambiguity remains regarding the adsorption mechanism at the catalyst surface(Langmuir-Hinshelwood or Eley-Rideal)and the adsorbed substrate groups.To address this,we prepared a Ni/Co electrode for the electrooxidation of 5-hydroxymethylfurfural(HMF)into 2,5-furandicarboxylic acid(FDCA)through a corrosion reaction and electro-reduction pathway.HMF conversion reached 100.00%,FDCA yield reached 96.82%,and Faradic efficiency(FE)reached 92.14%.Meaningfully,utilizing in-situ spectroscopy and electrochemical methods,this work provided valuable insights into active sites and catalyst surface adsorption. 展开更多
关键词 ELECTROCATALYSIS ELECTROCHEMISTRY 2 5-Furandicarboxylicacid 5-HYDROXYMETHYLFURFURAL Biomass
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Multifunctional MOF@COF Nanoparticles Mediated Perovskite Films Management Toward Sustainable Perovskite Solar Cells
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作者 Yayu Dong jian zhang +6 位作者 Hongyu zhang Wei Wang Boyuan Hu Debin Xia Kaifeng Lin Lin Geng Yulin Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期195-208,共14页
Although covalent organic frameworks(COFs)with highπ-conjugation have recently exhibited great prospects in perovskite solar cells(PSCs),their further application in PSCs is still hindered by face-to-face stacking an... Although covalent organic frameworks(COFs)with highπ-conjugation have recently exhibited great prospects in perovskite solar cells(PSCs),their further application in PSCs is still hindered by face-to-face stacking and aggregation issues.Herein,metal-organic framework(MOF-808)is selected as an ideal platform for the in situ homogeneous growth of a COF to construct a core-shell MOF@COF nanoparticle,which could effectively inhibit COF stacking and aggregation.The synergistic intrinsic mechanisms induced by the MOF@COF nanoparticles for reinforcing intrinsic stability and mitigating lead leakage in PSCs have been explored.The complementary utilization ofπ-conjugated skeletons and nanopores could optimize the crystallization of large-grained perovskite films and eliminate defects.The resulting PSCs achieve an impressive power conversion efficiency of 23.61%with superior open circuit voltage(1.20 V)and maintained approximately 90%of the original power conversion efficiency after 2000 h(30-50%RH and 25-30℃).Benefiting from the synergistic effects of the in situ chemical fixation and adsorption abilities of the MOF@COF nanoparticles,the amount of lead leakage from unpackaged PSCs soaked in water(<5 ppm)satisfies the laboratory assessment required for the Resource Conservation and Recovery Act Regulation. 展开更多
关键词 Perovskite solar cells Covalent organic frameworks Metal-organic frameworks Lead leakage Stability
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Global patterns and ecological drivers of taxonomic and phylogenetic endemism in angiosperm genera
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作者 Hong Qian Brent D.Mishler +1 位作者 jian zhang Shenhua Qian 《Plant Diversity》 SCIE CAS CSCD 2024年第2期149-157,共9页
Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here... Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment. 展开更多
关键词 ANGIOSPERM Current climate ENDEMISM Historical climate change Topographic heterogeneity
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Comparing the efficacy and safety of low,medium,and high dosages of selexipag for treating pulmonary hypertension:A systematic review and meta-analysis
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作者 Shang Wang Yi Yan +8 位作者 jian zhang Ping Yuan Ci-Jun Luo Hong-Ling Qiu Hui-Ting Li jian Xu Lan Wang Tian-Lan Li Rong jiang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期56-70,共15页
Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypert... Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension(PAH),we performed a sys-tematic review and meta-analysis.Methods:Studies assessing PAH risk stratification indices,such as the World Health Organization functional class(WHO-FC),six-minute walk distance(6MWD),N-terminal pro-B-type natriuretic peptide(NT-proBNP)level,right atrial pressure(RAP),cardiac index(CI)and mixed venous oxygen saturation(SvO2),were included.Results:Thirteen studies were included.Selexipag led to improvements in the 6MWD(MD:24.20 m,95%CI:10.74-37.67),NT-proBNP(SMD:-0.41,95%CI:-0.79-0.04),CI(MD:0.47 L/min/m^(2),95%CI:0.17-0.77)and WHO-FC(OR:0.564,95%CI:0.457-0.697).Subgroup analysis demonstrated that all three dosages improved the 6MWD.A moderate dosage led to improvements in the CI(MD:0.30 L/min/m^(2),95%CI:0.15-0.46)and WHO-FC(OR:0.589,95%CI:0.376-0.922).Within 6 months of treatment,only the WHO-FC and CI were significantly improved(OR:0.614,95%CI:0.380-0.993;MD:0.30 L/min/m^(2),95%CI:0.16-0.45,respectively).More than 6 months of treatment significantly improved the 6MWD,WHO-FC and NT-proBNP(MD:40.87 m,95%CI:10.97-70.77;OR:0.557,95%CI:0.440-0.705;SMD:-0.61,95%CI:-1.17-0.05,respectively).Conclusions:Low,medium,and high dosages of selexipag all exhibited good effects.When treatment lasted for more than 6 months,selexipag exerted obvious effects,even in the low-dosage group.This finding is important for guiding individualized treatments. 展开更多
关键词 individualized treatments META-ANALYSIS prostacyclin receptor agonist risk stratification systematic review
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An Industrial Intrusion Detection Method Based on Hybrid Convolutional Neural Networks with Improved TCN
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作者 Zhihua Liu Shengquan Liu jian zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期411-433,共23页
Network intrusion detection systems(NIDS)based on deep learning have continued to make significant advances.However,the following challenges remain:on the one hand,simply applying only Temporal Convolutional Networks(... Network intrusion detection systems(NIDS)based on deep learning have continued to make significant advances.However,the following challenges remain:on the one hand,simply applying only Temporal Convolutional Networks(TCNs)can lead to models that ignore the impact of network traffic features at different scales on the detection performance.On the other hand,some intrusion detection methods considermulti-scale information of traffic data,but considering only forward network traffic information can lead to deficiencies in capturing multi-scale temporal features.To address both of these issues,we propose a hybrid Convolutional Neural Network that supports a multi-output strategy(BONUS)for industrial internet intrusion detection.First,we create a multiscale Temporal Convolutional Network by stacking TCN of different scales to capture the multiscale information of network traffic.Meanwhile,we propose a bi-directional structure and dynamically set the weights to fuse the forward and backward contextual information of network traffic at each scale to enhance the model’s performance in capturing the multi-scale temporal features of network traffic.In addition,we introduce a gated network for each of the two branches in the proposed method to assist the model in learning the feature representation of each branch.Extensive experiments reveal the effectiveness of the proposed approach on two publicly available traffic intrusion detection datasets named UNSW-NB15 and NSL-KDD with F1 score of 85.03% and 99.31%,respectively,which also validates the effectiveness of enhancing the model’s ability to capture multi-scale temporal features of traffic data on detection performance. 展开更多
关键词 Intrusion detection industrial internet channel spatial attention multiscale features dynamic fusion multi-output learning strategy
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Microwave electrometry with Rydberg atoms in a vapor cell using microwave amplitude modulation
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作者 郝建海 贾凤东 +9 位作者 崔越 王昱寒 周飞 刘修彬 张剑 谢锋 白金海 尤建琦 王宇 钟志萍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期65-74,共10页
We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the m... We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the microwave(MW)electric field.In addition to the two zero-crossing points interval△f_(zeros),the dispersion signal has two positive maxima with an interval defined as the shoulder interval△f_(sho),which is theoretically expected to be used to measure a much weaker MW electric field.The relationship of the MW field strength E_(MW)and△f_(sho)is experimentally studied at the MW frequencies of 31.6 GHz and 9.2 GHz respectively.The results show that△f_(sho)can be used to characterize the much weaker E_(MW)than that of△f_(zeros)and the traditional EIT–AT splitting interval△f_(m);the minimum E_(MW)measured by△f_(sho)is about 30 times smaller than that by△f_(m).As an example,the minimum E_(MW)at 9.2 GHz that can be characterized by△f_(sho)is 0.056 mV/cm,which is the minimum value characterized by the frequency interval using a vapor cell without adding any auxiliary fields.The proposed method can improve the weak limit and sensitivity of E_(MW)measured by the spectral frequency interval,which is important in the direct measurement of weak E_(MW). 展开更多
关键词 quantum sensor Rydberg atoms electromagnetically induced transparency amplitude modulation
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A-site assisted perovskite crystallization via ion-exchange MOFs for high efficient and stable perovskite solar cells
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作者 Xingrui zhang jian zhang +5 位作者 Wei Wang Boyuan Hu Yayu Dong Debin Xia Kaifeng Lin Yulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期436-442,I0011,共8页
Here,a novel strategy is proposed targeting the volatility of A-site cations and the disordered arrangement of perovskite grains through employing Cs~+contained metal-organic frameworks In-aip(Cs)obtained by ion-excha... Here,a novel strategy is proposed targeting the volatility of A-site cations and the disordered arrangement of perovskite grains through employing Cs~+contained metal-organic frameworks In-aip(Cs)obtained by ion-exchange and crystalline transform.Interatomic forces between Cs-O atoms split the pore channels of the pristine In-aip,endowing In-aip(Cs)with multidimensional charge transport channels,In addition,the partially freed Cs~+in the interlayer compensates for the vacancy of A-site cations during the perovskite preparation process.The In-aip(Cs)modified perovskite films have a flat morphology,large grains and excellent optoelectronic properties.Benefiting from the high-quality perovskite films and faster charge extraction,the In-aip(Cs)-modified PSCs achieved a champion PCE of 23.03%,superior to the In-aip-modified(22.29%)and control device(21.13%),More importantly,the unencapsulated PSCs modified with In-aip(Cs)exhibited outstanding humidity and thermal stability.Over a period of almost 1000 h,the unencapsulated In-aip(Cs)-modified device retained 85%of its initial PCE after storing in a glove box at 85℃,and retained 87%of the primary PCE upon storage in ambient condition at 25℃under a humidity of 40%. 展开更多
关键词 Metal-organic frameworks PSCs Stability Defect passivation
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