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中国化学会·第十三届全国物理有机化学学术会议

作者：成贵娟 Nikolaos Drosos Bill Morandi walter thiel Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 香港中文大学(深圳)

通过生物质转化合成平台化合物由于其可持续性获得广泛的关注,其中多元醇是生物质转化得到的一种常见原料化学品。由于多个羟基的存在,多元醇的选择性脱氧还原反应一直是研究的难点。对于1,2-邻二醇,传统过渡金属催化方法通常还原所有...

通过生物质转化合成平台化合物由于其可持续性获得广泛的关注,其中多元醇是生物质转化得到的一种常见原料化学品。由于多个羟基的存在,多元醇的选择性脱氧还原反应一直是研究的难点。对于1,2-邻二醇,传统过渡金属催化方法通常还原所有羟基或者2-位羟基。这里我们采用量子化学计算研究了首例B(CF)催化1,2-邻二醇的选择性1-位羟基脱氧还原反应。

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四苯乙烯衍生物的激发态失活途径

四苯乙烯衍生物的激发态失活途径

Nonlinear response of a multidirectional negative-stiffness isolation system via semirecursive multibody dynamic approach

第十三届全国量子化学会议

作者：高远君常雪萍刘向洋李全松崔刚龙 walter thiel 教育部理论计算光化学重点实验室北京师范大学化学学院北京理工大学化学化工学院马克思-普朗克煤炭研究所

聚集诱导发光(AIE)现象的发现为有机发光材料领域打开了一扇新的大门。其中,四苯乙烯(TPE)是常见的构建AIE化合物的基元。取代基位置的改变,TPE化合物的光物理性质也会随之变化,如四(间-甲基)苯乙烯(TPE-4mM)的荧光量子产率(Фf)为0.1%... 详细信息

聚集诱导发光(AIE)现象的发现为有机发光材料领域打开了一扇新的大门。其中,四苯乙烯(TPE)是常见的构建AIE化合物的基元。取代基位置的改变,TPE化合物的光物理性质也会随之变化,如四(间-甲基)苯乙烯(TPE-4mM)的荧光量子产率(Фf)为0.1%,而四(对-甲基)苯乙烯(TPE-4oM)的Фf为64.3%,荧光量子产率比前者提高了600多倍!为了揭示这一现象产生的原因,我们采用静态电子结构计算,并结合非绝热动力学模拟研究了两种TPE衍生物的激发态失活机理。计算结果表明:相邻苯环的光环化过程是TPE-4mM激发态失活的主要途径,而这一过程在TPE-4oM中受到阻碍。我们期望这一发现为新型AIE分子的设计提供更多理论依据和理论指导。

关键词： AIE 四苯乙烯衍生物静态电子结构计算非绝热动力学模拟光环化

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International Journal of Mechanical System Dynamics 2024年第3期4卷 258-277页

作者： Wei Dai Biagio Carboni Giuseppe Quaranta Yongjun Pan walter Lacarbonara College of Mechanical and Vehicle Engineering Chongqing UniversityChongqingChina Department of Structural and Geotechnical Engineering Sapienza University of RomeRomeItaly

This paper investigates an innovative negative-stiffness device(NSD)that modifies the apparent stiffness of the supported structure for seismic *** NSD comprises a lower base on the bottom and a cap on the top,together with a connecting rod,vertical movable wall,and compressed elastic spring,as well as circumferentially arranged,pretensioned external ropes,and inclined shape memory *** configuration can deliver negative stiffness and energy dissipation in any direction within the horizontal plane.A numerical model of the device is developed through a two-step semirecursive method to obtain the force–displacement characteristic *** a model is first validated through comparison with the results obtained via the commercial software ***,a large parametric study is performed to assess the role and the influence of each design variable on the overall response of the proposed *** guidelines are drawn from this analysis to guide the system design and optimization.

关键词： multibody system negative stiffness semirecursive approach seismic protection vibration isolation

The Paris 2024 Olympic and Paralympic Games

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Journal of Sport and Health Science 2024年第6期13卷 717-718页

作者： walter Herzog Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N 1N4Canada

The first modern Olympic Games took place in Athens in *** in those early days of the Olympics only amateur and gentleman athletes were allowed to participate,today Olympic athletes are highly trained professionals often dedicating decades of preparation for the chance to compete in the Olympic *** sharp contrast to these highly trained athletes,the world’s population becomes less physically active on average,resulting in an obesity epidemic with associated metabolic syndrome and increased mortality through non-communicable diseases(e.g.,Collins et al.^(1)).

关键词： Olympic allowed sharp

Intraocular pressure before and after capsulorhexis using two viscoelastic substances and two surgical approaches in enucleated porcine eyes

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1156-1160页

作者： Chiraz Ben Abdallah walter Sekundo Markus SLadewig Daniel M.Handzel Augenzentrum Osthessen Fulda 36037Germany University Eye Hospital Philipps-University Marburg 35043Germany University Eye Hospital Philipps-University Campus FuldaFulda 36043Germany

AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this ***:Prospective experimental WetLab study carried out on enucleated porcine *** was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss Meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss Meditec AG,Germany;hydroxy propylmethylcellulosis(HPMC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the ***:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the *** use of different OVDs made no *** the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm *** difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD ***:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine *** use of different OVD has no significant influence on IOP drop.

关键词： cataract surgery ophthalmosurgical viscoelastic device intraocular pressure capsulorhexis enucleated porcine eye

A simple laboratory method for the generation of mixed brominated-chlorinated paraffin single chain mixtures

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Emerging Contaminants 2024年第2期10卷 90-97页

作者： walter Vetter Clara Hägele Karin Herrmann Tobias Schulz Sina Schweizer University of Hohenheim Institute of Food Chemistry(170b)Garbenstr.2870599StuttgartGermany

Brominated-chlorinated paraffins(Br-CPs)are a comparably new compound class that features both Cl and Br atoms on one or several alkane *** to legal restrictions in the use of conventional chlorinated paraffins(CPs),Br-CPs have the potential to become emerging ***,their determination is hampered by the lack of suitable reference ***,we present a simple synthesis procedure with single chain alkanes that leads to Br-CPs with∼4–8 chlorine and 1 to 4 bromine substituents according to gas chromatography with electron capture negative ion mass spectrometry(GC/ECNI-MS).The single-chain Br-CP mixtures were obtained by the shared chlorination and bromination of eight single-chain alkanes(C10 to C17)at two reaction times,*** carbon content of the 16 single-chain Br-CP products,determined by elemental analysis(EA),ranged from 30.8 to 43.8%.The typical hump peak known from CPs was detected with GC with flame ionization detection(GC/FID),electron capture detection(GC/ECD)and GC/*** complexity indicated that low-resolution mass spectrometry is not sufficient for an adequate analysis of Br-CPs.A mathematical formula was developed which allows to calculate all possible combinations of Br and Cl that are in line with the carbon *** proton magnetic resonance spectroscopy(1H NMR)spectra showed similarities to the ones of CPs with one chemical shift range for protons on nonhalogenated carbons and one for protons with one halogen on the same carbon.

关键词： NMR) mixtures alkanes

Pumping-induced Well Hydraulics and Groundwater Budget in a Leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 477-490页

作者： ZHUANG Chao LÜChenyang YAN Long LI Yabing ZHOU Zhifang WANG Jinguo DOU Zhi walter A.ILLMAN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of Earth and Environmental Sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical *** investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard *** of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater *** the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer *** using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage.

关键词： hydrogeology aquitard vertical heterogeneity semi-analytical solution well hydraulics groundwater budget

Impact of pre- and peri-operative risk factors on length of stay and hospital readmission following minimally-invasive partial nephrectomy

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Asian Journal of Urology 2024年第1期11卷 72-79页

作者： Vanessa A.Lukas Rahul Dutta Ashok K.Hemal Matvey Tsivian Timothy E.Craven Nicholas A.Deebel David D.thiel Ram Anil Pathak Brigham and Women's Hospital Division of UrologyDepartment of Surgery75 Francis StreetBostonMAUSA Atrium Health Wake Forest Baptist Medical Center Department of Urology1 Medical Center BlvdWinston-SalemNCUSA Mayo Clinic Florida Department of Urology4500 San Pablo RoadJacksonvilleFLUSA

Objective:We conducted an analysis of the American College of Surgeons National Surgical Quality Improvement Program database for minimally-invasive partial nephrectomy cases reported with the goal to identify pre-and peri-operative variables associated with length of stay(LOS)greater than 3 days and readmission within 30 ***:Records from 2008 to 2018 for“laparoscopy,surgical;partial nephrectomy”for prolonged LOS and readmission cohorts were *** analysis with Chi-square,t-tests,and multivariable logistic regression analysis with odds ratios(ORs),p-values,and 95%confidence intervals assessed statistical ***:Totally,20306 records for LOS greater than 3 days and 15854 for readmission within 30 days were *** and multivariable analysis exhibited similar *** LOS greater than 3 days,undergoing non-elective surgery(OR=5.247),transfusion of greater than four units within 72 h prior to surgery(OR=5.072),pre-operative renal failure or dialysis(OR=2.941),and poor pre-operative functional status(OR=2.540)exhibited the strongest statistically significant *** hospital readmission within 30 days,loss in body weight greater than 10%in 6 months prior to surgery(OR=2.227)and bleeding disorders(OR=2.081)exhibited strongest statistically significant ***:Multiple pre-and peri-operative risk factors are independently associated with prolonged LOS and hospital readmission within 30 days of surgery using the American College of Surgeons National Surgical Quality Improvement Program *** the risks factors that can potentially be improved prior to minimally-invasive partial nephrectomy is crucial to informing patient selection,optimization strategies,and patient education.

关键词： Minimally-invasive partial nephrectomy The American College of Surgeons National Surgical Quality Improvement Program Lengthof stay Hospital readmission