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Role of nitric oxide in cerebral ischemia/reperfusion injury:A biomolecular overview
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作者 Roberto Anaya-Prado Abraham I Canseco-Villegas +14 位作者 Roberto Anaya-Fernández Michelle Marie Anaya-Fernandez Miguel A Guerrero-Palomera Citlalli Guerrero-Palomera Ivan F Garcia-Ramirez Daniel Gonzalez-Martinez Consuelo Cecilia Azcona-Ramírez Claudia Garcia-Perez Airim L Lizarraga-Valencia Aranza Hernandez-Zepeda Jacqueline F Palomares-Covarrubias Jorge HA Blackaller-Medina Jacqueline Soto-Hintze Mayra C Velarde-Castillo Dayri A Cruz-Melendrez 《World Journal of Clinical Cases》 SCIE 2025年第10期9-13,共5页
Nitric oxide(NO)is a gaseous molecule produced by 3 different NO synthase(NOS)isoforms:Neural/brain NOS(nNOS/bNOS,type 1),endothelial NOS(eNOS,type 3)and inducible NOS(type 2).Type 1 and 3 NOS are constitutively expre... Nitric oxide(NO)is a gaseous molecule produced by 3 different NO synthase(NOS)isoforms:Neural/brain NOS(nNOS/bNOS,type 1),endothelial NOS(eNOS,type 3)and inducible NOS(type 2).Type 1 and 3 NOS are constitutively expressed.NO can serve different purposes:As a vasoactive molecule,as a neurotransmitter or as an immunomodulator.It plays a key role in cerebral ischemia/reperfusion injury(CIRI).Hypoxic episodes simulate the production of oxygen free radicals,leading to mitochondrial and phospholipid damage.Upon reperfusion,increased levels of oxygen trigger oxide synthases;whose products are associated with neuronal damage by promoting lipid peroxidation,nitrosylation and excitotoxicity.Molecular pathways in CIRI can be altered by NOS.Neuroprotective effects are observed with eNOS activity.While nNOS interplay is prone to endothelial inflammation,oxidative stress and apoptosis.Therefore,nNOS appears to be detrimental.The interaction between NO and other free radicals develops peroxynitrite;which is a cytotoxic agent.It plays a main role in the likelihood of hemorrhagic events by tissue plasminogen activator(t-PA).Peroxynitrite scavengers are currently being studied as potential targets to prevent hemorrhagic transformation in CIRI. 展开更多
关键词 Nitric oxide Cerebral ischemia/reperfusion injury Nitric oxide synthase Reactive nitrogen species NITROSYLATION
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Research on the use of sintering flue gas desulphurization gypsum as a cement retarder 被引量:2
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作者 CHEN Ronghuan WANG Ruyi SHI Lei 《Baosteel Technical Research》 CAS 2010年第2期13-15,共3页
The characteristics of the desulphurized gypsum produced in the flue gas desulphurization (FGD) process of the Baosteel sintering plant are investigated in this study. According to the technical and quality requirem... The characteristics of the desulphurized gypsum produced in the flue gas desulphurization (FGD) process of the Baosteel sintering plant are investigated in this study. According to the technical and quality requirements of gypsum in the cement industry ,the feasibility of using desulphurized gypsum as a cement retarder is also studied. The results show that desulphurized gypsum can be used as a cement retarder instead of natural gypsum. 展开更多
关键词 SINTERING desulphurization gypsum cement retarder
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Research and development of hot-rolled ultra-high strength steel at Baosteel 被引量:1
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作者 ZHENG Lei ZHANG Aiwen TANG Wenjun 《Baosteel Technical Research》 CAS 2010年第2期48-53,共6页
The effects of the composition and cooling process on the microstructures and properties of hot-rolled ultra-high strength low alloy (HSLA) steel, complex phase steel and martensite steel were studied in the laborat... The effects of the composition and cooling process on the microstructures and properties of hot-rolled ultra-high strength low alloy (HSLA) steel, complex phase steel and martensite steel were studied in the laboratory. And S700MC and MP1200 ultra-high strength steels were trial produced at the 1 880 mm hot-rolling line of Baosteel. Compared with conventional hot-rolled high strength products,the idea that water is alloy was applied in the newly developed hot-rolled ultra-high strength steel. By the use of the economical composition design and controlled cooling after hot-rolling effectively,ultra-high strength steel of different steel grades can be obtained. 展开更多
关键词 ultra-high strength low alloy steel complex phase steel martensite steel
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Research on the trajectory of non-metal inclusions with the flow in the mold during the solidification of continuous casting slabs
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作者 LIU Xufeng ZHENG Hongguang WANG Yan 《Baosteel Technical Research》 CAS 2011年第1期51-55,共5页
By means of the numerical simulation method,the mathematical model of inclusions movement in the mold is established under the condition of austenitic and fen-itic stainless steel slab production. According to the sim... By means of the numerical simulation method,the mathematical model of inclusions movement in the mold is established under the condition of austenitic and fen-itic stainless steel slab production. According to the simulation results, the main zones for inclusion particles accumulation were found and many factors that affected floating-up probability of inclusion particles were identified. These factors include the inclusion particle size, the casting speed and the slab width, etc. It is believed that the inclusion particle size is the key one among these factors. 展开更多
关键词 stainless steel continuous casting slab INCLUSION flow field numerical simulation
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Research on the application of the wet scrubber on the BSSF slag processing system at Baosteel
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作者 LI Yongqian LIU Yin XIAO Yongli 《Baosteel Technical Research》 CAS 2009年第3期38-40,共3页
Based on the analysis results of the dust size distribution of flue gas from Baosteel's short-flow (BSSF) slag processing system and the mechanism of the wet scrubber,a wet scrubber system was designed and installe... Based on the analysis results of the dust size distribution of flue gas from Baosteel's short-flow (BSSF) slag processing system and the mechanism of the wet scrubber,a wet scrubber system was designed and installed in the No. 1 BSSF slag processing system at Baosteel. The results show that the dust removal efficiency of the previous system that had conventional water nozzles was only 69% with a liquid-gas ratio of 0.79 L/m^3 ,while the dust removal efficiency reached 94% when three sets of high-efficiency dual phase spray guns were installed inside both the flue and the chimney. For the latter system,the liquid-gas ratio was 0. 84 L/m^3 ,and the dust concentration in the cleaned emissions reduced to less than 40 mg/m^3. 展开更多
关键词 slag processing wet scrubber NOZZLE particle size distribution dust removal efficiency
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The research on the decomposition and softening-meltingproperties of iron ore by TG-DSC
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作者 QI Wei LI Xianwei SHEN Hongbiao ZHU Yaping 《Baosteel Technical Research》 CAS 2012年第2期8-12,共5页
13 kinds of iron ores (6 from Australia and 7 from Brazil) were studied on their properties concerning CW (Combined Water) decomposition, FezO3 decomposition and softening-melting in air atmosphere through the cha... 13 kinds of iron ores (6 from Australia and 7 from Brazil) were studied on their properties concerning CW (Combined Water) decomposition, FezO3 decomposition and softening-melting in air atmosphere through the characterization method of TG-DSC (Thermogravimetry-Differential Scanning Caloremetry ). The experimental results of the Australian ores and Brazilian ores differ in terms of the initial temperature, temperature range and endothermic amount of CW decomposition,and besides, the content of CW. It is estimated that for every percent increase of CW content in sintering raw material, the extra thermal amount absorbed in the process is about 1.83 x 104 kJ, which equals to the thermal capacity of 0.625 kg of standard coal burning up completely. As to the decomposition of Fe203 ,the initial temperatures, terminal temperatures and temperature ranges of the Australian and Brazilian ores are quite close. However, the endothermic amount of Fe2O3 decomposition of the two turns out rather different: the endothermic capacity of Fe2O3 decomposition of the Australian ores is greater than that of the Brazilian ores. Furthermore, the liquid amount generated in the softening-melting process is closely related to the SiO2 content in iron ore. The higher SiO2 content the ore contains, the more liquid volume it will generate in the softening-melting process of iron ore. 展开更多
关键词 iron ore TG-DSC CW decomposition Fe2O3 decomposition softening-melting properties
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Application research on feedback control based on Dahlin algorithm for coiling temperature of hot strip
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作者 WU Jianfeng WANG Xiaobo LIU Ye 《Baosteel Technical Research》 CAS 2012年第4期38-40,共3页
To improve the precision of the coiling temperature and the performance of the feedback control system with long pure time delay on hot strip mills, we analyzed the design process of the Dahlin algorithm in detail. Th... To improve the precision of the coiling temperature and the performance of the feedback control system with long pure time delay on hot strip mills, we analyzed the design process of the Dahlin algorithm in detail. The coiling temperature curves controlled by the PID algorithm and Dahlin algorithm were simulated and compared, which showed that the control precision with the Dahlin algorithm was higher than that with the PID algorithm. That was further verified by the production practice. 展开更多
关键词 Dahlin algorithm coiling temperature feedback control
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Numerical simulation research of dimension variation in heavy plate during quenching and tempering process
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作者 ZHANG Qingfeng JIANG Hongsheng 《Baosteel Technical Research》 CAS 2012年第4期47-50,共4页
The dimension variation of B610E steel during the quenching and tempering process was simulated by ABAQUS,the coefficient of heat transfer during quenching was verified by the buried thermocouple test and the trend of... The dimension variation of B610E steel during the quenching and tempering process was simulated by ABAQUS,the coefficient of heat transfer during quenching was verified by the buried thermocouple test and the trend of the dimension variation during the quenching process was also calculated by ABAQUS. It was shown by the comparison of simulated results and industrially measured results that only the simulation of thickness and width variation was accurate, while length variation needed further simulation. Besides, the dimension variation trend was identical with the measured results. 展开更多
关键词 heavy plate quenching and tempering process dimension variation numerical simulation
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Experimental research on hot-tearing crack sensitivity
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作者 RUAN Xiaoming ROBERT Pierer +1 位作者 SHI Chunyue MEI Feng 《Baosteel Technical Research》 CAS 2012年第3期18-23,共6页
Hot-tearing cracks usually form near the solidus temperature. It is caused by a combination of tensile stress and metallurgical embrittlement. In order to quantify embrittlement and to incorporate it in the thermal-st... Hot-tearing cracks usually form near the solidus temperature. It is caused by a combination of tensile stress and metallurgical embrittlement. In order to quantify embrittlement and to incorporate it in the thermal-stress analysis, many different criteria have been developed. Among them,the submerged split-chill tensile (SSCT) test is an efficient one. This paper tries to use SSCT to estimate the critical strain of hot tearing for some steels. 展开更多
关键词 SSCT hot-tearing crack critical strain
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Walking for health during pregnancy:A literature review and considerations for future research
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作者 Christopher P.Connolly Scott A.Conger +4 位作者 Alexander H.K.Montoye Mallory R.Marshall Rebecca A.Schlaff Sylvia E.Badon James M.Pivarnik 《Journal of Sport and Health Science》 SCIE 2019年第5期401-411,共11页
Walking is the most commonly chosen type of physical activity(PA)during pregnancy and provides several health benefits to both mother and child.National initiatives have promoted the importance of walking in general,b... Walking is the most commonly chosen type of physical activity(PA)during pregnancy and provides several health benefits to both mother and child.National initiatives have promoted the importance of walking in general,but little emphasis is directed toward pregnant women,the majority of whom are insufficiently active.Pregnant women face a variety of dynamic barriers to a physically active lifestyle,some of which are more commonly experienced during specific times throughout the pregnancy experience.Walking is unique in that it appears resistant to a number of these barriers that limit other types of PA participation,and it can be meaningfully integrated into some transportation and occupational activities when leisure-time options are unavailable.Preliminary intervention work suggests that walking programs can be effectively adopted into a typical pregnancy lifestyle.However,a great deal of work remains to administer successful pregnancy walking interventions,including developing and using validated methods of PA and walking assessment.This narrative review discusses the unique advantages of walking during pregnancy,provides recommendations for future intervention work,and outlines the need for pregnancy-focused community walking initiatives.Standard search procedures were followed to determine sources from the literature specific to walking during pregnancy for use in each section of this review. 展开更多
关键词 AMBULATORY activity Exercise behavior Maternal-fetal HEALTH PREGNANT women
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An intersectional gender analysis of familial and socio-cultural drivers of inequitable scientific career progression of researchers in Sub-Saharan Africa
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作者 Millicent L.Liani Isaac K.Nyamongo +1 位作者 Justin Pulford Rachel Tolhurst 《Global Health Research and Policy》 2021年第1期180-195,共16页
Background:Sub-Saharan Africa(SSA)suffers from a dearth of concrete information on the causes of women’s under-representation in scientific research workforce particularly at higher levels compared with the wealth of... Background:Sub-Saharan Africa(SSA)suffers from a dearth of concrete information on the causes of women’s under-representation in scientific research workforce particularly at higher levels compared with the wealth of information that exists in the global north.The goal of this study was to illuminate familial and socio-cultural drivers that contribute to intersectional gender inequities in scientific career progression in SSA to inform strategies that could promote career equity for African scientific researchers.Methods:This study was nested within the context of‘Developing Excellence in Leadership,Training and Science in Africa’(DELTAS Africa)—a health-based scientific research capacity strengthening initiative.It adopted an exploratory qualitative cross-sectional study design.In-depth interviews were conducted among 58(32 Female and 26 Male)trainees/research fellows at various career stages,affiliated to three purposively selected African Research Consortia.The interviews were conducted between May and December 2018 in English.The data were analysed inductively based on emergent themes.Results:The study participants were nationals of thirteen SSA countries.More female than male participants had young children.Four themes were identified.They illustrate women’s and men’s characterisation of the normative career pathway and progression requirements which calls for significant‘time’commitments(theme 1),and how social power relations of gender within the family and wider society shapes their participation in scientific research activities(theme 2).This culminates in researchers’’differential experiences of navigating between the‘two different lives’—family and career,and the resultant implications for their career progression and personal well-being(theme 3).Women researchers made different and conscious trade-offs for navigating the‘two different lives’by utilising various metaphors such as the‘biological clock and career clock’,the‘glass ball and rubber ball’,and the concept of‘sacrifice’(theme 4).Conclusions:This study is the first of its kind to demonstrate how intersectional gender analysis through use of qualitative research methods may provide novel insights into the hidden familial and socio-cultural drivers of gender inequitable scientific research career progression.It offers important policy and practice measures and approaches for fostering career equity for women and men scientists within research capacity strengthening initiatives in SSA. 展开更多
关键词 Researchers’lived experiences Socio-cultural influences Family Gender equity Intersectional gender analysis Scientific career progression Sub-Saharan Africa Social power relations Research capacity strengthening
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Mobile health interventions for improving maternal and child health outcomes in South Africa:a systematic review
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作者 Elliot Mbunge Maureen Nokuthula Sibiya 《Global Health Journal》 2024年第3期103-112,共10页
Background:Maternal and child health(MCH)remains a significant public health concern globally despite previous efforts made to improve MCH services.Initiatives such as antenatal care,postnatal care services exclusive ... Background:Maternal and child health(MCH)remains a significant public health concern globally despite previous efforts made to improve MCH services.Initiatives such as antenatal care,postnatal care services exclusive breastfeeding,child vaccination and supplements have been rolled out to improve MCH outcomes.However,inadequate maternal healthcare,socioeconomic factors,obstetric haemorrhaging,complications of hypertension during pregnancy,lack of maternal information,poor universal health coverage and uptake of MCH services exacerbate maternal mortality and child mortality rates,especially in resource-constrained areas in many sub-Saharan African countries including South Africa.Objective:This study aimed to review mobile health(mHealth)interventions deployed to improve maternal and child health outcomes.Methods:The study adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses model to search and retrieve relevant literature from reputable,prominent electronic databases(Google Scholar,Scopus,PubMed,Embase,CINAHL,Web of Science,etc.).A total of 26 papers were selected and analyzed.Results:The findings revealed several mHealth interventions such as MomConnect,Mobile Alliance for Maternal Action,NurseConnect,ChildConnect,CommCare,Road to Health Application and Philani Mobile Video Intervention for Exclusive Breastfeeding have been utilized by healthcare workers and women to improve access to MCH services.However,inadequate digital infrastructure,digital divide,resistance to change,inadequate funding,language barriers,short message service and data costs,lack of digital skills and support,compatibility,scalability and interoperability issues,legislative and policy compliance,lack of mHealth awareness,data security and privacy concerns hinder uptake and utilisation of mHealth interventions.There is a need to scale up and sustain mHealth interventions and update existing regulatory framework,policies and strategies.Conclusion:mHealth interventions offer unprecedented opportunities to improve access to maternal information and substantially improve maternal and child health services.Stakeholder engagement and the development of sustainable funding strategies are important for successfully implementing and scaling mHealth projects while addressing existing and emerging key issues. 展开更多
关键词 Mobile health(mHealth) Child health Maternal health Digital health technologies South Africa
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Reflections on four decades of physical activity epidemiology
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作者 Barbara Sternfeld David R.Jacobs Jr. 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期608-610,共3页
In 1985,Public Health Reports published a series of papers prepared for a workshop sponsored by the Centers for Disease Control and Prevention(CDC).1 Building on the seminal work of Jeremy Morris and Ralph Paffenbarge... In 1985,Public Health Reports published a series of papers prepared for a workshop sponsored by the Centers for Disease Control and Prevention(CDC).1 Building on the seminal work of Jeremy Morris and Ralph Paffenbarger Jr.,who were among the first to use epidemiological methods to study physical activity(PA),2,3 the workshop itself was the result of a growing scientific understanding of the importance of“physical fitness and exercise for improving the health of the public”. 展开更多
关键词 SEMI WORKSHOP RALPH
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Effect of valence and spin state on ethane dehydrogenation in Fe-S-1 catalyst
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作者 Liusai Huang Yumeng Fo +6 位作者 Peng Zhang Shaojia Song Xinxin Zhang Xueqiu Wu Saeed Soltanali Jian Liu Weiyu Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期677-686,I0014,共11页
Light alkanes non-oxidative dehydrogenation is an attractive non-oil route for olefins production.The alkane dehydrogenation reaction is limited by thermodynamic equilibrium,and the C-H bond cleavage is commonly consi... Light alkanes non-oxidative dehydrogenation is an attractive non-oil route for olefins production.The alkane dehydrogenation reaction is limited by thermodynamic equilibrium,and the C-H bond cleavage is commonly considered as the rate-determined step.The valence state of metal sites in catalysts will influence the stabilization of the vital intermediate(i.e.,C_(x)H_(y)...M^(δ+)...H)during the C-H bond cleavage process,which in turn affects the catalytic reactivity.Herein,we explicitly investigated the effect of different valence states of framework-Fe in silicate-1 zeolite on ethane dehydrogenation reaction through the combination of experimental and theoretical study.Fe(Ⅱ)-S-1 and Fe(Ⅲ)-S-1 catalysts are successfully synthesized by ligand-assisted in situ crystallization method,In-situ C_(2)H_6-FTIR shows the higher coverage of hydrocarbon intermediates on Fe(Ⅱ)-S-1,Under the same evaluation co nditio n,Fe(Ⅱ)-S-1 exhibits a higher space time yield of ethylene.Density functional theory(DFT)results reveal that the more coordinate-unsaturated and electron-enriched Fe(Ⅱ)sites boost the first C-H bond activation by slight deformation and efficient electron donation with C_(2)H_(5)^(*)species.Remarkably,the second C-H bond cleavage on Fe(Ⅱ)-S-1 undergoes a spin-crossing process from quintet state to triplet state,which involves a two-electro n-two-orbital interaction,further promoting the formation of ethylene.Microkinetic analysis is consistent with the experimental and DFT results.This work could provide methodology for elucidating the effect of metal valence states on catalytic performance as well as offer guidance for designing more efficient Fe-zeolite catalysts. 展开更多
关键词 IRON Ethane dehydrogenation Electron-enriched Spin crossover DFT
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Mono Ethanol Amine (MEA) Pulping of Wheat Straw: An Environmentally Friendly Suggestion for the Fluff Pulp Production
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作者 Saeed Ismaeilimoghadam Saeed Mahdavi +2 位作者 Mehdi Pourhashemi Afsaneh Shahraki Mehdi Jonoobi 《Journal of Renewable Materials》 EI CAS 2024年第10期1771-1789,共19页
This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production.For this purpose,mono ethanol amine(MEA)was selected as a de-lign... This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production.For this purpose,mono ethanol amine(MEA)was selected as a de-lignification agent at three levels of 50:50,25:75,and 15:85(MEA/water,W/V%),and soda-AQ 14 W/V%was used as a reference pulping.To investigate the optimal refining intensity,the obtained pulp was passed through a single disk laboratory refiner from 0 to 6 times and in two different consistencies(1.5 and 2.5 W/V%).Total yield,kappa number,ash content,and the Schopper-Riegler(SR°)freeness of the prepared pulps were investigated.Finally,hand sheets with a targeted basic weight of 70 g/m^(2) were made according to the related standards.The hand sheets were characterized using Fourier transform infrared(FTIR)spectroscopy and a field emission scanning electron microscope(FE-SEM).Sheet density,brightness,and mechanical properties such as burst,tensile,and tear indices were also investigated.The FE-SEM photographs showed that the texture of the hand sheet became denser as the refining intensity increased.External fibrillation on the surface of the fibers was also observed,especially on those refined with 2.5%consistency.The results of the chemical composition of wheat straw indicated that wheat straw containing a high percentage of holocellulose is an excellent candidate for the production of fluff pulp.The total yield and kappa number of MEA pulps increased with the decrease in MEA concentration.FTIR results indicated the presence of a peak related to amino groups in the pulp related to MEA pulp.The results also indicated that the mechanical properties of the papers,except for the tear index,were enhanced as the intensity of refining and the pulp consistency during refining increased. 展开更多
关键词 Wheat straw mono ethanol amine fluff pulp CELLULOSE
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Effect of silica fume and glass powder for enhanced impact resistance in GGBFS-based ultra high-performance geopolymer fibrous concrete:An experimental and statistical analysis
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作者 G.Murali Anoop Kallamalayil Nassar +2 位作者 Madhumitha Swaminathan Parthiban Kathirvel Leong Sing Wong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期59-81,共23页
Solid waste recycling is an economically sound strategy for preserving the environment,safeguarding natural resources,and diminishing the reliance on raw material consumption.Geopolymer technology offers a significant... Solid waste recycling is an economically sound strategy for preserving the environment,safeguarding natural resources,and diminishing the reliance on raw material consumption.Geopolymer technology offers a significant advantage by enabling the reuse and recycling of diverse materials.This research assesses how including silica fume and glass powder enhances the impact resistance of ultra-high-performance geopolymer concrete(UHPGC).In total,18 distinct mixtures were formulated by substituting ground granulated blast furnace slag with varying proportions of silica fume and glass powder,ranging from 10%to 40%.Similarly,for each of the mixtures above,steel fibre was added at a dosage of 1.5%to address the inherent brittleness of UHPGC.The mixtures were activated by combining sodium hydroxide and sodium silicate solution to generate geopolymer binders.The specimens were subjected to drop-weight impact testing,wherein an examination was carried out to evaluate various parameters,including flowability,density at fresh and hardened state,compressive strength,impact numbers indicative of cracking and failure occurrences,ductility index,and analysis of failure modes.Additionally,the variations in the impact test outcomes were analyzed using the Weibull distribution,and the findings corresponding to survival probability were offered.Furthermore,the microstructure of UHPGC was scrutinized through scanning electron microscopy.Findings reveal that the specimens incorporating glass powder exhibited lower cracking impact number values than those utilizing silica fume,with reductions ranging from 18.63%to 34.31%.Similarly,failure impact number values decreased from 8.26%to 28.46%across glass powder contents.The maximum compressive and impact strength was recorded in UHPGC,comprising 10%silica fume with fibres. 展开更多
关键词 Silica fume Glass powder Impact strength Steel fibre GGBFS Weibull analysis Microstructure
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CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening
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作者 Seo Yeon K. Orite Bryn Higuchi +1 位作者 Hyo-Chun Yoon Lana H. Gimber 《Open Journal of Radiology》 2024年第2期92-101,共10页
Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone min... Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies. 展开更多
关键词 OSTEOPOROSIS Bone Mineral Attenuation CT Threshold
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Basic regulatory science behind drug substance and drug product specifications of monoclonal antibodies and other protein therapeutics
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作者 Patanachai K.Limpikirati Sorrayut Mongkoltipparat +7 位作者 Thinnaphat Denchaipradit Nathathai Siwasophonpong Wudthipong Pornnopparat Parawan Ramanandana Phumrapee Pianpaktr Songsak Tongchusak Maoxin Tim Tian Trairak Pisitkun 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期785-804,共20页
In this review,we focus on providing basics and examples for each component of the protein therapeutic specifications to interested pharmacists and biopharmaceutical scientists with a goal to strengthen understanding ... In this review,we focus on providing basics and examples for each component of the protein therapeutic specifications to interested pharmacists and biopharmaceutical scientists with a goal to strengthen understanding in regulatory science and compliance.Pharmaceutical specifications comprise a list of important quality attributes for testing,references to use for test procedures,and appropriate acceptance criteria for the tests,and they are set up to ensure that when a drug product is administered to a patient,its intended therapeutic benefits and safety can be rendered appropriately.Conformance of drug substance or drug product to the specifications is achieved by testing an article according to the listed tests and analytical methods and obtaining test results that meet the acceptance criteria.Quality attributes are chosen to be tested based on their quality risk,and consideration should be given to the merit of the analytical methods which are associated with the acceptance criteria of the specifications.Acceptance criteria are set forth primarily based on efficacy and safety profiles,with an increasing attention noted for patient-centric specifications.Discussed in this work are related guidelines that support the biopharmaceutical specification setting,how to set the acceptance criteria,and examples of the quality attributes and the analytical methods from 60 articles and 23 pharmacopeial monographs.Outlooks are also explored on process analytical technologies and other orthogonal tools which are on-trend in biopharmaceutical characterization and quality control. 展开更多
关键词 Biopharmaceutical analysis Biopharmaceutical quality control Biopharmaceutical specifications Monoclonal antibodies Protein therapeutics Regulatory science
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A novel DFN-DEM approach to simulate long-term behavior of crystalline rock under effects of glacial climate conditions
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作者 Friederike Tiedtke Heinz Konietzky Fabien Magri 《Deep Resources Engineering》 2024年第1期53-67,共15页
The safety assessment of nuclear waste repositories is a critical yet challenging task.Several processes acting on different time scales and multiphysical couplings must be taken into account.The complexity of such as... The safety assessment of nuclear waste repositories is a critical yet challenging task.Several processes acting on different time scales and multiphysical couplings must be taken into account.The complexity of such assessments often requires integrating different software into a single numerical workflow.This study focuses on the long-term behavior of fractured rock masses and the alteration of the hydrogeological system under changing global climate conditions.The investigated impacts include the response of the rock mass due to heating of a generic repository,development of permafrost,and advance and retreat of an ice-shield.To represent THM processes on a timescale of~100,000 years in crystalline rock,a novel DFN-DEM modelling approach has been developed.The modelling approach combines two numerical software tools.The thermomechanical calculations are carried out using the distinct element method(DEM)based tool 3DEC[1].The flow field and the hydraulic heads in the fracture network are calculated with the DFN-tool DFN.Lab[2].A proprietary script allows to couple and update parameters and variables that are needed to perform THM calculations linking the two different tools.The long-term THM simulations are tested on a generic model of crystalline rock that includes deterministic fault zones as well as a stochastic DFN as the key feature of the hydrogeological system.The modelling approach allows to analyze the behavior of the fracture network including fracture growth and the development of flow pathways within the fracture network as a response to the external THM impacts.The results of the simulations show that the superposition of the different THM processes favors the development of preferential flow pathways along large-scale faults during cold climate conditions. 展开更多
关键词 Nuclear safety Numerical workflow Geo-mechanical coupling FRACTURES
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An Insight Survey on Sensor Errors and Fault Detection Techniques in Smart Spaces
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作者 Sheetal Sharma Kamali Gupta +2 位作者 DeepaliGupta Shalli Rani Gaurav Dhiman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2029-2059,共31页
The widespread adoption of the Internet of Things (IoT) has transformed various sectors globally, making themmore intelligent and connected. However, this advancement comes with challenges related to the effectiveness... The widespread adoption of the Internet of Things (IoT) has transformed various sectors globally, making themmore intelligent and connected. However, this advancement comes with challenges related to the effectiveness ofIoT devices. These devices, present in offices, homes, industries, and more, need constant monitoring to ensuretheir proper functionality. The success of smart systems relies on their seamless operation and ability to handlefaults. Sensors, crucial components of these systems, gather data and contribute to their functionality. Therefore,sensor faults can compromise the system’s reliability and undermine the trustworthiness of smart environments.To address these concerns, various techniques and algorithms can be employed to enhance the performance ofIoT devices through effective fault detection. This paper conducted a thorough review of the existing literature andconducted a detailed analysis.This analysis effectively links sensor errors with a prominent fault detection techniquecapable of addressing them. This study is innovative because it paves theway for future researchers to explore errorsthat have not yet been tackled by existing fault detection methods. Significant, the paper, also highlights essentialfactors for selecting and adopting fault detection techniques, as well as the characteristics of datasets and theircorresponding recommended techniques. Additionally, the paper presents amethodical overview of fault detectiontechniques employed in smart devices, including themetrics used for evaluation. Furthermore, the paper examinesthe body of academic work related to sensor faults and fault detection techniques within the domain. This reflectsthe growing inclination and scholarly attention of researchers and academicians toward strategies for fault detectionwithin the realm of the Internet of Things. 展开更多
关键词 ERROR fault detection techniques sensor faults OUTLIERS Internet of Things
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