检索结果-南通市图书馆

Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab Osman Antonio Pizzi bertrand Charrier Institute of Engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan ENSTIB-LERMAB University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and Engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ***(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOE at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13C NMR MALDI-ToF

A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2024年第4期12卷 721-736页

作者： Wadah Mohammed Zeinab Osman Salah Elarabi bertrand Charrier Institute of Analytical Sciences and Physical-Chemistry for the Environment and Materials-Xylomat University of Pau and the Adour RegionE2S UPPACNRSIPREM-UMR 5254Mont de Marsan40004France Institute of Engineering Research and Materials Technology(IERMT) National Center for Research(NCR)Ministry of Higher Education and Scientific ResearchKhartoum11111Sudan Faculty of Industries Engineering and Technology University of GeziraGezira State21111Sudan

The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and *** thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the *** this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy *** chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)*** total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the *** evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were *** chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%*** FTIR curves demonstrated a notable similarity among the *** TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton *** DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast *** higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,*** three fibers have a high potential for biocomposites and bioenergy material manufacturing.

关键词： Bagasse kenaf bast fibers cotton stalks TGA DSC FTIR

From the unknown to spotlight:newly identified hormone adjusts hepatic cholesterol synthesis to dietary uptake

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第7期9卷 2845-2847页

作者： Yakum bertrand Nkeh Resul Gökberk Elgin Gesine Saher Project Group Biology of Lipids Department of NeurogeneticsMax Planck Institute for Multidisciplinary SciencesGöttingenGermany

In a study published in Cell,Hu and colleagues discovered that the signaling activity of the intestinal hormone Cholesin leads to the attenuation of hepatic cholesterol synthesis in response to intestinal absorption thereby maintaining homeostatic levels of circulating cholesterol.1 These findings have major translational implications as they provide a potential new target for the management of hypercholesterolemia and associated disorders.

关键词： cholesterol hepatic synthesis

Deciphered: Whole-Process People's Democracy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Beijing Review 2024年第43期67卷 18-19页

作者： Arnaud bertrand 不详

In the West,skepticism often arises when China describes its political system as-a democracy,specifically a"wholeprocess people's democracy."However,this skepticism is frequently rooted in a lack of understanding about what China means by the term,how it differs from liberal democracy,and why the Chinese Government considers it an effective system for the country.

关键词： system arise Whole

Recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao RuiLong Guo Yong Wei bertrand Bonfond Denis Grodent BinZheng Zhang William R.Dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University Department of Earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of Earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. Recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at Earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(Guo RL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; Guo RL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

A high-power electromagnetic source for disabling improvised explosive devices

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2024年第2期9卷 403-409页

作者： Laurent Ariztia Njomza Ibrahimi Alexey Zhabin Antoine Silvestre de Ferron Marc Rivaletto Edson Martinod Valérie bertrand Bucur Novac Laurent Pécastaing Universite de Pau et des Pays de l’Adour E2S UPPASIAMEPauFrance XLIM UMR CNRS BriveLimogesFrance CISTEME LimogesFrance Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK

Ultra-wideband(UWB)microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter-terrorism *** authors present the main findings of a research dedicated to the development of a pulsed power-driven electromagnetic field source for disabling improvised explosive devices(IED).The pulsed power generator driving the source is a 13-stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV,with a pulse repetition frequency(PRF)of up to 100 *** generator is coupled to a bipolar pulse forming line,providing bipolar pulses with a dV/dt of around 1.6 MV/*** pulsed power system feeds an array composed of 16 Koshelev-type UWB antennas through an impedance matching *** resulting electromagnetic source is capable to produce pulsed electric fields(PEFs)having a figure-of-merit(FOM)of 1 ***,practical experiments were carried out to study the effects of the PEFs on *** targets used in the present study are M2B type flashbulbs,known to have the same susceptibility as the US army M6 *** configurations of wires(shielded,twisted,etc)with different lengths were used in connecting items inside these *** tests were performed by placing the flashbulbs at different distances to determine the essential parameters(i.e.,amplitude,duration,and frequency range)of the PEFs required to trigger *** overview of the experimental campaign and the main findings are also presented followed by conclusions.

关键词： power bipolar source

Fe-Ti Oxide Mineralization in the XV Intrusion,Bafq Mining District,Central Iran:Insights from Mineralogy,Mineral Chemistry and S Isotopic Data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2024年第5期35卷 1704-1719页

作者： Sakine Amraei Majid Ghasemi Siani Mohammad Yazdi Liang Qiu bertrand Moine Minghua Ren Department of Inorganic Geology and Water Faculty of Earth SciencesShahid Beheshti UniversityTehran Q9XV+XG7Iran Department of Geochemistry Faculty of Earth SciencesKharazmi UniversityTehran PC3G+QPJIran State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China Université Clermont Auvergne CNRSIRDOPGCLaboratoire Magmas et VolcansAubiere F-63178France Department of Geoscience University of NevadaLas Vegas NV 89154USA

The mafic-ultramafic intrusion in the XV anomaly area,contains magmatic Fe-Ti oxides±(p)ore,is located in the Bafq mining district in the Central *** consists of cumulate and layered Fe-Ti-bearing gabbros and *** mineral assemblages include clinopyroxene,Fe-Ti oxides,plagioclase,amphibole,apatite and sulfides(pyrite and chalcopyrite).The Fe-Ti oxides mainly consist of magnetite-titanomagnetite and ilmenite,which occurred as disseminated,intergrowth,lamellae(trellis and sandwich textures)and *** in the gabbroic rocks is from the near end-member of Fe_(3)O_(4)(<1 wt.%TiO_(2))to titanomagnetite containing up to 8 wt.%TiO_(2)(about3.73 wt.%to 26.84 wt.%Ulvospinel(X_(Usp))).Magnetite in pyroxenite rocks is characterized with TiO_(2)range from 0.46 wt.%to 3.14 wt.%(X_(Usp)varied from 1.76 wt.%to 10.46 wt.%).The abundances of V_(2)O_(3)range from 0.03 wt.%to 1.29 wt.%and 0.24 wt.%to 1.00 wt.%for gabbro and pyroxenite,respectively.X_(Usp)contents of magnetite show insignificant correlations with Al_(2)O_(3)and *** average XIlmin the ilmenite of gabbro is 92%,whereas it is 90.37%in the pyroxenite *** MgO and V_(2)O_(3)contents show a slightly positive correlation with TiO_(2)in *** composition of clinopyroxenes in gabbro and pyroxenite rocks fall in the diopside to augite field with Mg#ranging from 67 to 98 and 74 to 96,*** both rock types,amphiboles are mainly pargasite and rarely *** in pyroxenite rocks is clustered in the labradorite to andesine fields with a compositional ranges of An46-69and in gabboic rocks fall in two fields with compositional ranges of albite with An0.65-5.95and labradorite with ***δ34S isotopic values cover a limited range from+3.15‰to+4.10‰V-CDT consistent with magmatic ***-Ti mineralization is formed in two stages,minor inclusions of Fe-Ti oxide minerals in the pyroxene and plagioclase crystallized in the early magmatic stage,whereas interstitial oxide

关键词： mafic-ultramafic intrusion Fe-Ti oxides gravitational settling mineral chemistry Bafq mining district Central Iran mineral deposits

Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： Jérémy Raffin Yves Rolland Annelise Genoux Guillaume Combes Mikael Croyal bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group Institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'Epidémiologie et de Recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'Institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy ***1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains ***,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP *** examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these ***:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were ***1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year *** linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 *** analyses were conducted to examine whether apoA-I mediated these *** linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in ***:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly med

关键词： Aging Apolipoprotein Bioenergetics Exerkine Mitochondria

Physico-Chemical Characterization of Some Honeys from the Savannah-Gallery Forest Complex and Primary Forest in Gabon

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2024年第7期14卷 1904-1917页

作者： Charline Obone Madi Guirema Abaker Silas Davy Mbadinga Boubala Estelle dumont Gino Boussiengui-Boussiengui Alexis Nicaise Lepengue Dpartement Sciences Fondamental de lIngnieur Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon Dpartement de Biochimie Facult des Sciences Universit des Sciences et Techniques de Masuku Franceville Gabon LAboratoire de Recherche Multidisciplinaire en Environnement (LARME) USTM Franceville Gabon Dpartement de Phytotechnologie Institut National Suprieur dAgronomie et de Biotechnologies Universit des Sciences et Techniques de Masuku Franceville Gabon

Honey harvesting throughout beekeeping is a technology recently introduced in Gabon comparing to the other African countries well known in international honey trade. The purpose of this study is to contribute to the knowledge of the quality of multi-flower honeys from the savannah-gallery forest complex and primary forest not well documented in Gabon. Physical and chemical parameters of different honeys were analyzed using the official methods of analysis of the Association of Official Analytical Chemists. The results of physico-chemical analysis show variations in pH (3.4 to 3.9), free acidity (37.12 to 76.65 meq∙kg−1), water content (17.49% to 21.21%), electrical conductivity (0.64 to 1.24 mS∙cm−1), density (1.02 to 1.03) and total sugar content (77% to 82%). These variations were significantly different (p < 0.05) between certain honeys, but independent of the type of ecosystem considered. The pH values confirmed the botanical origin of the five honeys. The physico-chemical parameters of the honeys show significant correlations (p < 0.05). Moisture content is negatively correlated with conductivity (r = −0.628), pH (r = −0.631), density (r = −0.552) and total sugar content (r = −0.890). Conductivity is positively correlated with free acidity (r = 0.688) and total sugar content (r = 0.776), and negatively correlated with water content (r = −0.628). All honeys were in line with Codex Alimentarius standards, except for 3 types of honey (M1, M2 and M4) for free acidity and electrical conductivity, showing possible fermentation of these honeys.

关键词： Physico-Chemical Parameters Honey Gabon Codex Alimentarius