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Simulated photo-degradation of dissolved organic matter in lakes revealed by three-dimensional excitation-emission matrix with regional integration and parallel factor analysis

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Journal of Environmental Sciences 2020年第4期32卷 310-320页

作者： Jin zhang Fanhao Song Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai School of Environmental and Safety Engineering Changzhou UniversityJiangsu 213164China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Water Sciences Beijing Normal UniversityBeijing 100875China Department of Chemistry Beijing Normal UniversityBeijing 100875China Stockbridge School of Agriculture University of MassachusettsAmherstMA01003USA

Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(bh) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic *** the FRI analysis,fulvic-like and humic-like materials were the main constituents for both bh-FDOM and *** individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after *** multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(Radj2)(0.963-0.998).The photo-degradation rate constants(kn) showed differences of three orders of magnitude,from 1.09 × 10-6 to 4.02 × 10-4 min-1,and half-life of multi-order model(T1/2n)ranged from 5.26 to 64.01 *** decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(PⅠ,n) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(PⅡ,n,while the largest decrease ratio was found for C3 components,and the lowest T1/2n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during *** research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM.

关键词： Fluorescent dissolved organic matter Photo-degradation Fluorescence regional integration Parallel factor analysis Three-dimensional excitationemission matrix Multi-order kinetic models

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Improving the ammonia synthesis activity of Ru/CeO_(2) through enhancement of the metal–support interaction

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Journal of Energy Chemistry 2021年第9期30卷 403-409页

作者： Chunyan Li Yuying Shi Zecheng zhang Jun Ni Xiuyun Wang Jianxin Lin Bingyu Lin Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350002FujianChina

The metal–support interactions induced by high-temperature hydrogen reduction have a strong influence on the catalytic performance of ceria-supported Ru catalysts. However, the appearance of the strong metal–support interaction leads to covering of the Ru species by Ce suboxides, which is detrimental to the ammonia synthesis reaction that requires metallic species as active sites. In the present work, the interaction between Ru and ceria in the Ru/CeO_(2) catalyst was induced by Nabh_(4) treatment. Nabh_(4) treatment enhanced the fraction of metallic Ru, proportion of Ce^(3+), content of exposed Ru species, and amount of surface oxygen species. As a result, a larger amount of hydrogen species would desorb by the H_(2)-formation pathway and the strength of hydrogen adsorption would be weaker, weakening the inhibition effect of the hydrogen species on ammonia synthesis. In addition, the strong electronic metal–support interaction aids in nitrogen dissociation. Consequently, Ru/CeO_(2) with Nabh_(4) treatment showed higher ammonia synthesis rates than that with only hydrogen reduction.

关键词： Ammonia synthesis Na bh4treatment Metal–support interaction Ru/CeO_(2)

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High energy product of isotropic bulk Sm-Co/α-Fe(Co)nanocomposite magnet with multiple hard phases and nanoscale grains

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Journal of Materials Science & Technology 2021年第29期88卷 183-188页

作者： Shuo Li Longfei Ma Jinkui Fan Jianping Yang Qiang Zheng Baoru Bian Jian zhang Juan Du Institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai200444China Ningbo Institute of Material Technology&Engineering Chinese Academy of SciencesNingbo315201China

Nanocomposite magnets consisting of hard and soft magnetic phases have potential applications to be the next generation of permanent magnets with very high energy product and less expensive rare-earth *** it is still a big challenge to obtain bulk magnets with ideal microstructure and high *** this work,two-step warm processing at relative low temperatures had been adopted to obtain nearly theoretical density bulk nanocomposite magnets from amorphous/nanocrystalline powder *** nanostructures consisting of multiple Sm-Co hard phases(SmCo_(5)as main phase,SmCO_(3),SmCo_(7),Sm_(2)Co_(17)as minor phases)and 25 wt%α-Fe(Co)soft phase,nanoscale grain size below 20 nm for both the hard phase and soft phase,and the diffusion of Fe and Co compositions had been obtained in bulk isotropic *** the ideal nanostructures,a high coercivity of 5.9 kOe,M_(r)/M_(s)value of 0.78 and a high square degree of demagnetization curve S=0.47 were *** of these factors together brought a new record-high energy product(bh)_(max)of 23.6 *** results make an important step toward fabricating novel nanostructure with high performance.

关键词： Hard/soft phase nanocomposite Isotropic bulk Magnetic properties Grain size Phase constitution

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Hyperaccretion after the Blandford-Znajek Process:A New Model for GRBs with X-Ray Flares Observed in Early Afterglows

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Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 404-410页

作者： Wei-Hua Lei Ding-Xiong Wang Yuan-Chuan Zou Lei zhang Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We propose a three-stage model with Blandford-Znajek （BZ） and hyperaccretion process to interpret the recent observations of early afterglows of Gamma-Ray Bursts （GRBs）. In the first stage, the prompt GRB is powered by a rotating black hole （bh） invoking the BZ process. The second stage is a quiet stage, in which the BZ process is shut off, and the accretion onto the bh is depressed by the torque exerted by the magnetic coupling （MC） process. Part of the rotational energy transported by the MC process from the bh is stored in the disk as magnetic energy. In the third stage, the MC process is shut off when the magnetic energy in the disk accumulates and triggers magnetic instability. At this moment, the hyperaccretion process may set in, and the jet launched in this restarted central engine generates the observed X-ray flares. This model can account for the energies and timescales of GRBs with X-ray flares observed in early afterglows.

关键词： accretion, accretion disks - black hole physics - magnetic fields - gammarays bursts

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穗分化末期-灌浆初期干旱胁迫对优质食味粳稻根系形态和叶片光合特性的影响

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中国水稻科学 2024年第1期38卷 33-47页

作者：景秀周苗王晶王岩王旺王开郭保卫胡雅杰邢志鹏许轲张洪程扬州大学江苏省作物栽培生理重点实验室/江苏省粮食作物现代产业技术协同创新中心/扬州大学、水稻产业工程技术研究院江苏扬州225009 江苏省丹阳市农业农村局江苏丹阳212300

【目的】研究穗分化末期至灌浆初期土壤干旱对优质食味粳稻根系形态生理与叶片光合特性的影响,为水稻抗旱栽培提供理论参考。【方法】以南粳9108和丰粳1606为供试材料,分别在穗分化末期至籽粒灌浆初期20 d(BAH)、穗分化末期10 d(bh)与... 详细信息

【目的】研究穗分化末期至灌浆初期土壤干旱对优质食味粳稻根系形态生理与叶片光合特性的影响,为水稻抗旱栽培提供理论参考。【方法】以南粳9108和丰粳1606为供试材料,分别在穗分化末期至籽粒灌浆初期20 d(BAH)、穗分化末期10 d(bh)与灌浆初期10 d(AH)设置轻度干旱(LD,ψsoil=−20±5 kPa)、重度干旱(SD,ψsoil=−40±5 kPa)及常规水分(CK)处理。【结果】1)在处理结束当天、处理结束后10 d、穗后30 d与成熟期,根长、根表面积、根体积、根尖数、根干质量与根系活力均表现为SDbh、AH时段SD与CK差异显著,LD与CK无显著差异。处理结束后10 d、穗后30 d与成熟期,BAH时期SD与CK差异显著,除根尖数外LD与CK差异不显著,bh时期SD根系部分指标与CK差异显著,AH时期水分处理间无显著差异。2)在处理结束时、处理结束后10 d、穗后30 d与成熟期,剑叶净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO_(2)浓度(Ci)、最大光化学效率(Fv/Fm)、光化学猝灭系数(qp)均表现为SDbh、AH时段SD各指标均与CK差异显著,LD与CK差异不显著。在处理结束后10 d、穗后30 d与成熟期,BAH时段SD与CK差异显著,LD与CK差异多不显著,bh时段SD的Pn、Tr、Fv/Fm较CK差异显著,而AH时段各指标在水分处理间差异多数不显著。3)三处理时段下各胁迫处理间产量均表现为SDbh时段不同水分处理间差异显著,AH时段LD、CK间无显著差异,但二者均与SD差异显著。【结论】BAH时期轻度干旱、重度干旱均会抑制根系生长与叶片光合能力,显著降低产量,其中轻度干旱影响较小。bh时期土壤重度干旱时,根、叶形态生理指标在处理结束后难以恢复至对照水平,AH时期轻度干旱、重度干旱处理各指标在处理结束后能较快恢复。可见,在穗分化末期至灌浆初期,水稻根系和叶片生长对穗分化末期干旱胁迫更为敏感。

关键词：穗分化末期至灌浆初期优质食味粳稻干旱胁迫根系形态生理光合特性叶绿素荧光

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Chemical vapor deposited diamond with versatile grades:from gemstone to quantum electronics

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Frontiers of Materials Science 2022年第1期16卷 17-54页

作者： Yuting ZHENG Chengming LI Jinlong LIU Junjun WEI Xiaotong zhang Haitao YE Xiaoping OUYANG Institute for Advanced Materials and Technology(IAMT) State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Engineering University of LeicesterLeicester LE17RHUK School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Chemical vapor deposited(CVD)diamond as a burgeoning multifunctional material with tailored quality and characteristics can be artificially synthesized and controlled for various ***,the application-related“grade”concept associated with materials choice and design was gradually formulated,of which the availability and the performance are optimally *** this review,the explicit diversity of CVD diamond and the clarification of typical grades for applications,i.e.,from resplendent gem-grade to promising quantum-grade,were systematically summarized and discussed,according to the crystal quality and main consideration of ubiquitous nitrogen impurity content as well as major *** of those,from quantum-grade with near-ideal crystal to electronic-grade having extremely low imperfections and then to optical,thermal as well as mechanical-grade needing controlled flaws and allowable impurities,would competently fulfill the multi-field application prospects with appropriate choice in terms of cost and ***,wide range defects and impurities in the gem-grade diamond(only indicating single crystal),which are detrimental for technology applications,endows CVD crystals with fancy colors to challenge their natural counterparts.

关键词： CVD diamond synthesis and characterization quality and impurity grading application

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Effect of probucol on autophagy and apoptosis in the penile tissue of streptozotocin-induced diabetic rats

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Asian Journal of Andrology 2020年第4期22卷 409-413页

作者： Ke-Qin zhang Tao Tian Liang-Liang Hu Hao-Ran Wang Qiang Fu Department of Urology Shandong Provincial Hospital Affiliated to Shandong UniversityJinan 250021China Department of Urology Shandong Zaozhuang Municipal HospitalZaozhuang 277000China

Autophagy and apoptosis have been regarded as important processes in the development of diabetic erectile dysfunction(DMED).Probucol is considered to have anti-apoptotic effects,but its relationship with autophagy has not been *** aim of this study was to investigate the effects and mechanisms of probucol on erectile *** Sprague–Dawley(SD)male rats(12 weeks old)were fasted for 12 *** SD rats were injected with a single intraperitoneal injection of 60 mg kg−1 streptozotocin(STZ).Ten rats were given vehicle only and used as a sham *** 72 h,20 STZ-treated rats with random blood glucose concentrations consistently greater than 16.7 mmol l^−1 were used as successfully established diabetic *** diabetic rats were divided randomly into two groups and treated with a daily gavage of probucol at a dose of 0 or 500 mg kg^−1 for 12 *** treatment,the intracavernous pressure(ICP)was used to measure erectile function upon electrical stimulation of the cavernous *** euthanasia,penile tissue was examined using immunohistochemistry and Western blot to assess the protein levels of B-cell lymphoma-2(Bcl-2),BCL2-associated X(Bax),microtubule-associated protein light chain 3-II(LC3-II),mammalian target of rapamycin(mTOR),and sequestosome 1(P62).Caspase-3 activity was measured to determine apoptosis using a caspase-3 assay *** 12 weeks of treatment,the erectile function of the probucol group was significantly better than that of the DM group(P<0.05).Bax and LC3-II protein expression and caspase-3 activity were significantly lower in the probucol group than those in the DM group(all P<0.05),while Bcl-2,mTOR,and P62 protein expression levels were significantly higher than those in the DM group(all P<0.05).We demonstrated that probucol inhibited apoptosis and autophagy in STZ-induced diabetic rats.

关键词： apoptosis autophagy erectile dysfunction probucol

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Higgs and Bottom Quarks Associated Production at High Energy Colliders in the Littlest Higgs Model with T-Parity

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Communications in Theoretical Physics 2018年第3期69卷 297-302页

作者： Biao-Feng Hou Hua-Ying zhang Heng-Heng Bi College of Physics and Materials Science Henan Normal University Xinxiang 453007 China

In the littlest Higgs Model with T-parity,we discuss the Higgs production in association with bottom quarks at the LHC and future electron-positron *** calculate the cross sections of production channels pp→bb H,bb→H and bg→b H at 14 Te V LHC and the cross sections of production channel e^+e^-→bb H in(un)polarized beams at the lowest *** order to investigate the observability,we display some typical final state distributions in the Higgs to diphoton channel.

关键词： Higgs boson bottom quark littlest Higgs model with T-parity

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Carbon materials:The burgeoning promise in electronics

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International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 404-423页

作者： Yuting Zheng Junjun Wei Jinlong Liu Liangxian Chen Kang An Xiaotong zhang Haitao Ye Xiaoping Ouyang Chengming Li Institute for Advanced Materials and Technology(IAMT State Key Laboratory for Advanced Metals and MaterialUniversity of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Engineering University of LeicesterLeicester LE17RHUnited Kingdom School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Current electronic technology based on silicon is approaching its physical and scientific limits. Carbon-based devices have numer- ous advantages for next generation electronics (e.g., fast speed, low power consumption and simple process), that when combined with the unique nature of the versatile allotropes of carbon elements, are creating an electronics revolution. Carbon electronics are greatly advancing with new preparations and sophisticated designs. In this perspective, representatives with various dimensions, e.g., carbon nanotubes, graphene, bulk diamond, and their extraordinary performance, are reviewed. The associated state-of-the-art devices and composite hybrid all-carbon structures are also emphasized to reveal their potential in the electronics field. Advances in commercial production have improved the cost effi-ciency, material quality, and device design, accelerating the promise of carbon materials.

关键词： carbon materials nanotube graphene diamond electronic devices

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3D打印肾脏模型在软性输尿管镜技能培训中的应用价值

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现代泌尿外科杂志 2019年第11期24卷 923-926页

作者：张弋于澄钒张军晖闫伟肖河周学贤林燕丽 CHEW bh 北京大学国际医院泌尿外科北京102206 首都医科大学附属朝阳医院泌尿外科北京100043 首都医科大学附属同仁医院泌尿外科北京100730 北京协和医院泌尿外科北京100005 北京大学国际医院科教部北京102206 钻石医学中心温哥华总医院加拿大V5Z1M9

目的探讨新型3D打印肾脏模型在软性输尿管镜技能培训中的有效性。方法上尿路结石病例CTU数据经处理输出到3D打印机制作患者特异性的肾脏模型,以10分制Likert问卷量表以及专家与初学者模型操作表现(模型培训前、后)进行对比。结果5名专家... 详细信息

目的探讨新型3D打印肾脏模型在软性输尿管镜技能培训中的有效性。方法上尿路结石病例CTU数据经处理输出到3D打印机制作患者特异性的肾脏模型,以10分制Likert问卷量表以及专家与初学者模型操作表现(模型培训前、后)进行对比。结果5名专家和32名初学者纳入本研究,专家评价为总体有效性(9.6±0.5)分、图像质量(8.8±0.8)分、上尿路解剖(9.4±0.5)分、结石信息(9.8±0.4)分,以及对手术计划和培训的有效性(9.6±0.5)分。培训前,专家所有指标均显著优于初学者(P<0.003);培训后,初学者操作水平显著提高(P<0.001),探及肾盏和结石数目与专家的差别消失(P=0.228和P=0.980),探查时间和综合评分(GRS)也明显接近,初学者反馈评价均高于9分。结论图像后处理和3D打印生成肾脏模型可作为软性输尿管镜模拟培训的有效工具,可提高初学者操作水平,模型的表面、内容和构建效度得到验证。

关键词： 3D打印肾脏模型模拟培训软性输尿管镜尿路结石

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