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钒──多孔二氧化钛玻璃催化剂上的邻二甲苯氧化

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化学与粘合 1994年第4期16卷 240-243,217页

作者： CHEE YEE HONG,RALPH P.COONEY and russell f.howe(Chemistry Department,University of Auckland,Private Bag,Auckland New Zealard)

已经采用几种不同方法，把氧化钒负载在多孔氧化钛玻璃（ＰＴＧ）上。氮吸附—解吸附等温线和Ｘ—射线粉末衍射测定表明，浸渍方法在玻璃大孔中产生氧络钒类。在进行邻二甲苯氧化制邻苯二甲酸酐时，氧化钒—ＰＴＧ催化剂与通常的锐钛矿... 详细信息

已经采用几种不同方法，把氧化钒负载在多孔氧化钛玻璃（ＰＴＧ）上。氮吸附—解吸附等温线和Ｘ—射线粉末衍射测定表明，浸渍方法在玻璃大孔中产生氧络钒类。在进行邻二甲苯氧化制邻苯二甲酸酐时，氧化钒—ＰＴＧ催化剂与通常的锐钛矿或金红石负载的催化剂相比较，有相近的选择性和转化率，但是，其反应温度要低得多．生产邻苯二甲酸酐的催化剂活性随钒量增加而提高；邻二甲苯１００％的转化，邻苯二甲酸酐选择性为５０％，这种最好情况是在反应温度２８℃下实现的，所用催化剂含５．６％Ｖ（重／重）。

关键词：邻二甲苯氧化氧化钛玻璃钒催化剂

Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen Ryan P.russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

Knowledge and discriminatory attitudes towards HIV/AIDS among the women of reproductive age group of Pakistan using the Multiple Indicator Cluster Survey(MICS)

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Global Health Journal 2024年第2期8卷 74-82页

作者： Remsha Hussain russell Kabir School of Allied Health Faculty of HealthMedicine and Social CareAnglia Ruskin UniversityUnited Kingdom

Background Human immunodeficiency virus/acquired immunodeficiency syndrome(HIV/AIDS)has become a major worldwide public health issue,with a focus on developing *** having a very low HIV prevalence,South Asia faces serious issues with stigma and false information because of a lack of *** stigma highlights significant gaps in popular awareness while also sustaining unfavorable attitudes towards those living with HIV/*** is ranked second in South Asia for the rapidly increasing AIDS *** information and optimistic outlooks are essential for successful HIV/AIDS prevention,control,and *** false beliefs about how HIV/AIDS spreads lead to negative perceptions,which highlights the need to look into how women’s knowledge and attitudes about HIV/AIDS in Pakistan are influenced by sociodemographic traits and *** The purpose of this study is to evaluate Pakistani women’s discriminatory attitudes and level of awareness on HIV/*** study used data(the women in reproductive age 15-49 years’dataset)from the Pakistan Multiple Indicator Cluster Survey to conduct an analytical cross-sectional *** represent the respondents’attitudes and knowledge towards people living with HIV(PLHIV),two composite variables were developed and composite *** logistics regression was used to identify predictor variables and chi-square was used for bivariate *** The findings reveal that almost 90%of Pakistani women have poor knowledge and attitude with HIV/*** Punjab,72.8%of rural residents have low knowledge,whereas only 20.6%of young individuals(15-f *** is shown to be crucial,and“Higher”education is associated with superior *** dwellers in Khyber Pakhtunkhwa typically have more *** of HIV is positively correlated with education;those with higher education levels know a lot more(odds ratio[OR]=5.419).Similarly,quintil

关键词： HIV/AIDS PLHIV Knowledge Attitudes Women Pakistan

ARCADE 2 Spatial Roar, What Theory of Relation Reveals

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Journal of Modern Physics 2024年第5期15卷 690-719页

作者： russell Bagdoo Saint-Bruno-de-Montarville Quebec Canada

The theory of Relation provides an explanation for the Arcade 2 excess. It assumes that the isotropic radio emission measured by the Arcade 2 Collaboration, which is 5 - 6 times brighter than the expected contributions from known extra-galactic sources, is the residue of an immense primitive energy of ordinary matter released by a relativistic bang almost 100 million years after the big bang, which gave the mass-energy the missing gravity to activate contraction. This relativistic bang, via a Lorentz energy transformation, would have released enormous energy held to be the source of the powerful radio noise detected by the NASA researchers. This transformation would have simultaneously triggered the formation of the first stars from dense gas and the reionization of less dense neutral gas. This departs from the idea that continuous reionization began after the formation of the first stars. We emphasize the importance of primordial magnetic fields, which would have generated significant density fluctuations during recombination and acted as a direct seed for cosmic structures. The first stars and galaxies were bathed in strong magnetic fields that gave rise to the radio microwave din (boom) discovered by Arcade 2. These intense magnetic fields alter the trajectory of charged particles zooming near the speed of light, triggering the space roar and emitting radiation that forms a synchrotron radio background. The theory of Relation offers an alternative to the Lambda-CDM cosmological model, which has become the standard model of the big bang, which leads straight to the vacuum catastrophe.

关键词： Arcade 2 Excess Relativistic Bang Theory of Relation Lorentz Energy Transformation Cosmic Statics Cosmic Boom Synchrotron Radio Background Primordial Magnetic fields

Survival outcomes in early-onset oesophageal adenocarcinoma patients:A systematic review and meta-analyses

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World Journal of Gastroenterology 2024年第38期30卷 4221-4231页

作者： Ashleigh russell Shauna Mitchell Richard C Turkington Helen G Coleman Centre for Public Health Queen's University BelfastBelfast BT126BAUnited Kingdom Patrick G Johnston Centre for Cancer Research Queen's University BelfastBelfast BT71NNUnited Kingdom

BACKGROUND The incidence of oesophageal adenocarcinoma(OAC)has been reported to be increasing in many *** this trend,an increase in incidence of early-onset OAC,defined as OAC in adults aged under 50 years,has been *** is unclear whether survival outcomes for early-onset OAC patients differ from older age *** To investigate survival outcomes in early-onset OAC *** Ovid Medline and Embase were searched from inception to January 2022 for relevant studies relating to early-onset OAC and survival *** regarding the overall five-year survival and risk of death of younger and older patients with OAC were extracted and pooled using meta-analyses to produce pooled estimates and 95%CIs where *** Eleven studies which compared survival of early-onset OAC,defined as age at diagnosis off median and mean survival demonstrated conflicting results,with studies showing early-onset OAC patients having both better and worse outcomes compared to older age groups.A meta-analysis of five-year survival demonstrated similar outcomes across age groups,with 22%-25%of patients in the young,middle and older age groups alive after five years.A meta-analysis of four studies demon-strated that early-onset OAC patients did not have a significantly increased risk of death compared to middle-aged patients(hazard ratio 1.12,95%CI:0.85-1.47).INTRODUCTION There is concern that the incidence of oesophageal adenocarcinoma(OAC)in patients under 50,described as early-onset OAC,is ***,data regarding survival of younger patients with OAC is ***,while increasing age remains a major non-modifiable risk factor for cancer,the incidence of early-onset cancers,largely accepted to be in adults aged under 50 years,is increasing[1].This includes an observed increase in the incidence of gastrointestinal malignancies such as colorectal,oesophageal,gastric and he

关键词： Early-onset cancer Early-onset oesophageal adenocarcinoma Survival Cancer epidemiology Systematic review Meta-analysis

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

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Equal Opportunities

英语世界 2024年第4期 126-128页

作者： russell Evans

Pre-reading task Youaregoingtoreadanarticleabout ***,thinkaboutyourown *** equal opportunities policy? Why? Which groups of people do you think have been helped by equal opportunities law?

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Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

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结构化液体的设计、构筑与应用

高分子学报 2024年第5期55卷 485-508页

作者：封维潇 Thomas P.russell 史少伟北京化工大学化工资源有效利用国家重点实验室北京软物质科学与工程高精尖创新中心北京100029 Department of Polymer Science and Engineering University of MassachusettsAmherstMassachusetts 01003

结构化液体是近年来基于二元流体体系,利用固体粒子液/液界面自组装和堵塞相变构筑的一类非平衡态软物质材料,兼具固体的结构稳定性和液体的流动性.然而,受限于组装基元和成型方法,制备具有精准结构的智能结构化液体及衍生功能材料仍面... 详细信息

结构化液体是近年来基于二元流体体系,利用固体粒子液/液界面自组装和堵塞相变构筑的一类非平衡态软物质材料,兼具固体的结构稳定性和液体的流动性.然而,受限于组装基元和成型方法,制备具有精准结构的智能结构化液体及衍生功能材料仍面临挑战.我们课题组在该领域开展了大量研究工作,在发展界面调控新机制,制备液体/固体新材料,以及实现材料器件新突破等方面取得了系列创新成果.本专论从固体粒子界面自组装机制出发,重点阐述了一种利用纳米粒子和聚合物液/液界面共组装制备纳米粒子表面活性剂,进而构筑结构化液体的普适策略;总结归纳了结构化液体在响应性调控、高效精准构筑以及功能材料制备等方面的研究进展;并对该领域面临的机遇和挑战做出展望.

关键词：结构化液体纳米粒子表面活性剂液/液界面自组装