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American Journal of Analytical Chemistry 2015年第5期6卷 429-436页

作者： Sa'ib J. Khouri Department of Basic Sciences American University of Madaba Madaba Jordan

The apparent acid dissociation constant (Kc) of benzoic acid in water has been determined ti-trimetrically under ionic strength values between 0.00 and 0.50 mol·L﹣1 at a range of temperatures between 16°C and 41°C. The thermodynamic dissociation constant (as pKa) of benzoic acid was determined as 4.176 at 25°C. No regular correlation between pKa of benzoic acid and the temperature in the range was used. The values of pKa are inversely proportional to temperatures between 16°C and 30°C. In this range of temperature, the values of thermodynamic quantities () for the dissociation process of benzoic acid in water were calculated by using Van’t Hoff plot. For this case the dissociation was not favoured through entropy and enthalpy changes. The values of pKa are directly proportional to temperatures between 30°C and 41°C.

关键词： Benzoic Acid Ionic Strength Thermodynamic Dissociation Constant Salt Effect

Availability of elements for heterogeneous catalysis: Predicting the industrial viability of novel catalysts

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Chinese Journal of Catalysis 2018年第1期39卷 16-26页

作者： Anders B. Laursen Jens Sehested ib Chorkendorff Peter C. K. Vesborg Department of Physics Technical University of DenmarkFysikvej bygn.307DK‐2800 Kgs.LyngbyDenmark Haldor Topsoe A/S Haldor Topsoe Alle 1DK乚2800 Kgs.LyngbyDenmark

Growing concern regarding the sustainability of the chemical industry has driven the developmentof more efficient catalytic ***‐generation estimates of catalyst viability are based oncrustal abundance,which has severe ***,we propose a second‐generation approachto predicting the viability of novel catalysts prior to industrial implementation to benefit the globalchemical *** this prediction,we found that a correlation exists between catalyst consumptionand the annual production or price of the catalyst element for11representative industrialcatalytic *** on this correlation,we have introduced two new descriptors for catalystviability,namely,catalyst consumption to availability ratio per annum(CCA)and consumed catalystcost to product value ratio per annum(CCP).Based on evaluations of CCA and CCP for selected industrial reactions,we have grouped catalysts from the case studies according to viability,allowing the identification of general limits of viability based on CCA and *** the CCA and CCP and their comparing with the general limits of viability provides researchers with a novel framework for evaluating whether the cost or physical availability of a new catalyst could be *** have extended this analysis to calculate the predicted limits of economically viable production and product cost for new catalysts.?2018,Dalian Institute of Chemical Physics,Chinese Academy of *** by Elsevier *** rights reserved.

关键词： Heterogeneous catalysis Industrial catalysis Sustainability Element availability Catalyst Catalyst design Element abundance Scalability

Differences in Judo Attack Systems Between Weight Categories

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Journal of Science in Sport and Exercise 2023年第3期5卷 263-273页

作者： Daniel Brandão Kashiwagura Javier Courel-ibáñez Felipe Brandão Kashiwagura Marcus Fábio Agostinho Emerson Franchini Martial Arts and Combat Sports Research Group School of Physical Education and SportSport DepartmentUniversity of São PauloAv.Prof.Mello Morais65Cidade UniversitáriaSão PauloSP 05508-030Brazil Faculty of Sport Sciences University of MurciaMurciaSpain Brazilian Judo Confederation Rio de JaneiroBrazil

Purpose In judo,athletes compete based on weight categories,which are required to adapt the training process accordingly,but not enough research is present to understand their *** present study aimed to verify the differences in judo attack systems performed between the seven male weight categories in world-class *** A cohort of 5847 attack systems from 1106 international judo matches was *** Chi-square auto-matic interaction detector was used to identify the association between the variables tori approach(attacker),uke approach(defender),tori’s grip,stance and direction of *** The main results showed that:(1)the grip is the main predictor of attack systems;(2)laterality exerts a strong influence on attack systems;(3)the≤81 kg and>100 kg categories were differentiated by the use of unconventional grips;(4)the≤60 kg used more kenka-yotsu(opposite sides)right stance with the Only Right Hand grip;(5)the≤81 kg category used more the ai-yotsu(same side)left stance with the Only Left Hand *** The results reported from this study can help coaches and athletes in choosing the best technical-tactical actions when developing combat strategies.

关键词： Martial arts Decision tree Analysis Athletes Judoka Fight dynamics

Pressurized Liquid Extraction of Pigments from Chlamydomonas *** Chemical Characterization by HPLC–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi Yolanda García Carlos Almeida Carl Safi Nicole Engelen‑Smit Alejandro Cifuentes Jose A.Mendiola Elena ibáñez Applied Analytical Chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity Chlamydomonas sp. HPLC–DAD–APCI–MS/MS Pigments Pressurized liquid extraction Carotenoids

Shade coffee plantations maintain woody plant diversity and structure in a cloud forest landscape of southern Mexico

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Journal of Forestry Research 2021年第2期32卷 637-648页

作者： Edson AAlvarez-Alvarez R.Carlos Almazán-Nunez Fernando González-García Marlene Brito-Millán Alfredo Méndez-Bahena Sergio García-ibáñez Maestría en Recursos Naturales y Ecología Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico Laboratorio Integral de Fauna Silvestre Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Red Biología y Conservación de Vertebrados Instituto de EcologíaA.C.CP 91073 XalapaVeracruzMexico University of California Institute for Mexico and the United States(UC MEXUS) Cuerpo Académico Biodiversidad y Gestión Ambiental SustentableFacultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Biología de la Conservación Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Ecología Cuantitativa Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico

Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these ***,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these *** this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession *** each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was *** of species was analyzed using ordination methods,and alpha diversity was compared using Hill ***-seven woody species belonging to 40 families were *** richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle *** composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle *** results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.

关键词： Land uses Late succession Plant diversity Shade coffee Vegetation structure

Inflammatory bowel disease: A descriptive study of 716 local Chilean patients

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World Journal of Gastroenterology 2016年第22期22卷 5267-5275页

作者： Daniela Simian Daniela Fluxá Lilian Flores Jaime Lubascher Patricio ibánez Carolina Figueroa Udo Kronberg Raúl Acuna Mauricio Moreno Rodrigo Quera Academic Research Unit Clinica Las Condes Santiago 7591046 Chile Gastroenterology Departament Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Gastroenterology Department Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Colorectal Surgery Department Clinica Las Condes Santiago 7591046 Chile Laboratory of Oncology and Molecular Genetics Colorectal Surgery Clinica Las Condes Santiago 7591046 Chile

AIM: To demographically and clinically characterize inflammatory bowel disease (ibD) from the local registry and update data previously published by our ***: A descriptive study of a cohort based on a registry of patients aged 15 years or older who were diagnosed with ibD and attended the ibD program at Clínica Las Condes in Santiago, Chile. The registry was created in April 2012 and includes patients registered up to October 2015. The information was anonymously downloaded in a monthly report, and the information on patients with more than one visit was updated. The registry includes demographic, clinical and disease characteristics, including the Montreal Classification, medical treatment, surgeries and hospitalizations for crisis. Data regarding infection with Clostridium difficile (C. difficile) were incorporated in the registry in 2014. Data for patients who received consultations as second opinions and continued treatment at this institution were also ***: The study included 716 patients with ibD: 508 patients (71%) were diagnosed with ulcerative colitis (UC), 196 patients (27%) were diagnosed with Crohn’s disease (CD) and 12 patients (2%) were diagnosed with unclassifiable ibD. The UC/CD ratio was 2.6/1. The median age was 36 years (range 16-88), and 58% of the patients were female, with a median age at diagnosis of 29 years (range 5-76). In the past 15 years, a sustained increase in the number of patients diagnosed with ibD was observed, where 87% of the patients were diagnosed between the years 2001 and 2015. In the cohort examined in the present study, extensive colitis (50%) and colonic involvement (44%) predominated in the patients with UC and CD, respectively. In CD patients, non-stricturing/non-penetrating behavior was more frequent (80%), and perianal disease was observed in 28% of the patients. There were significant differences in treatment between UC and CD, with a higher use of corticosteroids, and immunosupp

关键词： Inflammatory bowel disease Crohn’ s disease Ulcerative colitis South America Latin America Chile Epidemiology

Interaction of cationic cyanine dye with algal alginates: evidence for a polymer bound dye dimer

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Journal of Biophysical Chemistry 2011年第4期2卷 380-385页

作者： Sa’ib J. Khouri Volker Buss 不详

Under certain conditions algal alginates bind pinacyanol chloride in the form of dimers – this is the conclusion drawn from a uv/vis and circular dichroism (CD) spectroscopic study of aqueous solutions of the dye in a 10-fold molar excess of the polysaccharide from different sources. With its easily detected features the dimer holds promise as a diagnostic tool for alginate conformational analysis. Binding of the strongly blue-shifted (maximum wavelength = 485 nm) dimer is probably mediated by the charged groups and involves guluronate units only. By using the peakFit program, the two overlapping excitonic absorption bands together with the optically inactive band resulted from the interaction of pinacyanol with a specific alginate concentration were separated. The standard Gibbs energy of the interaction was calculated as –27.02 ***–1. The dimers are sensitive against acid and divalent cations.

关键词： Guluronate Mannuronate Peakfit Association Constant Complexation Circular Dichroism

Circular Dichroism and Derivative Spectra Study of the Excitonic Aggregation of Pinacyanol by Aerosol-OT

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Open Journal of Physical Chemistry 2012年第1期2卷 34-40页

作者： Sa’ib J. Khouri Volker Buss Department of Chemistry American University of Madaba Madaba Jordan

Different structures are proposed for the complexes formed from the interaction between the cationic cyanine dye 1, 1’-diethyl-2, 2’-carbocyanine chloride (Pinacyanol chloride) and the anionic surfactant sodium bis (2-ethylhexyl) sul- fosuccinate (Aerosol-OT) in ethanol-water solutions. UV/vis and electronic circular dichroism (CD) spectra provide tools to study the concentration and solvent dependence of this interaction. The aggregation spectra of the dye are dominated by a strongly blue-shifted, sharp and single visible band, which appears at concentrations much below the critical micelle concentration (cmc) of Aerosol-OT. Above the cmc, the spectra in pure aqueous solution indicate disso- ciation into monomer and dimer species, and the system becomes completely empty of chirality. Two different CD spectra with a distinct isosbestic point are observed for complexes with different surfactant to dye ratios. Both the addi- tion of ethanol (more than 7.5%) and increasing the temperature retards the metachromatic process between the dye and Aerosol-OT. By using the peakFit program, the two overlapping excitonic absorption bands together with the optically inactive absorption band for one spectrum (the most optimal one) at a specific Aerosol-OT concentration were sepa- rated.

关键词： Cyanine Dye Pinacyanol Surfactant Aerosol-OT Aggregation Circular Dichroism Derivative Spectra

映在大理石上的德国故事(节译)——评德国建筑师施佩尔和他的建筑

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建筑学报 1999年第4期 9-13页

作者： Wht.,ib 方元中国海外兴业有限公司

当德国的包豪斯学院在１９３３年被关闭以后，德国现代建筑的命运就落在了纳粹的手中。在纳粹专制时代，建筑作为传达信息的媒体比建筑本身更重要。美的艺术形式与丑的政治目的联姻造成纳粹建筑的双重性格，希特勒的御用建筑师施佩尔利... 详细信息

当德国的包豪斯学院在１９３３年被关闭以后，德国现代建筑的命运就落在了纳粹的手中。在纳粹专制时代，建筑作为传达信息的媒体比建筑本身更重要。美的艺术形式与丑的政治目的联姻造成纳粹建筑的双重性格，希特勒的御用建筑师施佩尔利用现代商业建筑设计和舞台设计的技巧，把建筑变成了他们向德国人民和国际社会推销纳粹的商品。如今，经过半个世纪的时间，德国人民正在重新评价自己的历史。

关键词：纳粹建筑景框设计线性透视图网格建筑师

Enhancement of vitamin A combined vitamin D supplementation on immune response to Bacille Calmette-Guerin vaccine revaccinated in Chinese infants

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Asian Pacific Journal of Tropical Medicine 2014年第2期7卷 130-135页

作者： Ying Zheng Xue-Gang Li Qiu-Zhen Wang Ai-Guo Ma ib Christian Bygbjerg Yong-Ye Sun Yong Li Ming-Ci Zheng Xi Wang Institute of Human Nutrition Medical College of Qingdao Unirersity Department of International Health University of Copenhagen Department of Pediatrics.Guilin Medical College Affiliated Hospital Department of Orthopaedic Surgery The Sixth Affiliated Hospital of Sun Yat-sen University

Objective:To investigate whether there is an association between diameter of bacille CalmetteGuerin(BCG)sears and effect of purified protein derivative(PPD)reaction anil to determine whether vitamin A(VA)combined vitamin I)(VD)supplementation influences the immune response to BCG revueeinated in Chinese ***:A cross-section and 3-month community-randomised trial was conducted.A total of 5 629 infants at 3,6 and 12 months of age in Junan County of China were examined for BCG scar ***,597 revuccinated infants were randomly assigned to supplementation(n=307)and control(n=290)*** supplementation group were daily assigned to 1 500 IU VA and 500 IU VD for 3 *** all infants were subjected to skin test with ***:The diameter of BCG sears was positively con-elated with diameter of skin indurations of PPD(r=0.17,Pibute to the prevention of childhood tuberculosis.

关键词： Tuberculosis Bacille Calmette-Guerin Purified protein derivative Vitamin A Vitamin D Revaccination