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Geochemical assessment of a siliceous limestone sample for cement making

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Chinese Journal Of Geochemistry 2011年第1期30卷 33-39页

作者： Rao d.s. Vijayakumar T.V. Prabhakar s. Bhaskar Raju G. National Metallurgical Laboratory-Madras Centre CsIR Madras Complex Taramani Chennai-600 113 India

A low grade siliceous limestone sample from the Jayantipuram mine of Andhra Prad.s., India, has been investigated for its suitability for cement making. Petrological as well as X-ray diffraction pattern studies indicated that the limestone sample was crystalline and dominantly composed of calcite and quartz. They are simple in mineralogy, and yet they have variable silica and lime contents. Geochemical analysis results of twenty five hand picked.s.mples indicated that the limestone from the Jayantipuram mine shows a wide range of variations in LOI (29.94% to 40.64%), siO2 (6.14% to 27.18%), CaO (37.93% to 50.78%), Al2O3 (0.49% to 2.27%) and Fe2O3 (0.28% to 2.4%). MgO, K2O, Na2O, TiO2 and MnO2 are present in traces. CaO with LOI shows a strong positive correlation where as CaO with siO2 shows a strong negative correlation because of mineralogical factors. The chemical composition of the limestone reflects its mineralogical composition. The d.s.ribution of various elements in the acid.s.luble fraction has been studied by the factor analysis method in order to interpret in terms of their mineralogy, sedimentary environment and diagenesis. Mineralogy, recrystallization and other diagenetic changes are the main factors affecting the d.s.ribution of the elements and their mutual relationships in the limestone. The aim of this paper is also to analyze how significantly the two parameters, silica modulus and lime saturation factor, influence this low grade siliceous limestone sample from the Jayantipuram mine of Andhra Prad.s., India, for the cement making process from the geochemical data.

关键词：灰岩样品水泥生产地球化学硅质石灰石矿评估因子分析方法化学数据处理

Effect of coating material and lubricant on forming force and.s.rface defects in wire drawing process

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Transactions of Nonferrous Metals society of China 2011年第A1期21卷 104-110页

作者： s.M.BYON s.J.lee d.W.lee Y.H.lee Y.lee department of Mechanical Engineering Dong-A University department of Mechanical Engineering Chung-Ang University Wire Rod Research Group POSCO Technical Research Laboratories

A pilot wire drawing machine as well as wire end-pointing roller was developed. Using these machines, a wire drawing test for four different coating materials and two different lubricants was performed as the reduction ratio increased from 10% to 30%. Materials used for a substrate in this study are plain carbon steel （AIs11045） and ultra low carbon bainite steel. To compute the friction coefficient between the coating layer of wire and the surface of die lbr a specific lubricant, a series of finite element analyses were carried out. sEM observations were also conducted to investigate the surface defects of wire deformed. Results show that the behavior of drawing force varies with the lubricant-type at the initial stage of drawing. The powder-typed lubricant with a large particle causes the retardation of lull lubrication on the entire contact surface and the local delamination of coating layer on the wire surface. As the flow stress of a substrate increases, the delamination becomes severe.

关键词： coating lubricant wire drawing delamination

Plasma density measurement and downstream etching of silicon and.s.licon oxide in Ar/NF3 mixture remote plasma source

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Plasma science and Technology 2019年第6期21卷 52-57页

作者： H J YEOM d H CHOI Y s lee J H KIM d J sEONG s J YOU H C lee Korea Research Institute of standards and.s.ience(KRIss) Daejeon 34113 Republic of Korea department of Physics Chungnam National University Daejeon 34134 Republic of Korea

In this study,plasma density measurements were performed near the plume region of the remote plasma source (RPs) in Ar/NF3 gas mixtures using a microwave cutoff *** measured plasma density is in the range of 1010-1011 cm-3 in the d.s.harge conditions with RPs powers of 2-4 kW and gas pressures of 0.87-4 *** plasma density decreased with increasing gas pressures and RPs powers under various Ar/NF3 mixing *** decrease in the plasma density measured at the fixed measurement position (plume region) can be understood by the reduction of the electron energy relaxation length with increases in the gas pressures and mixing ratio of NF3/(Ar/NF3).We also performed downstream etching of silicon and.s.licon oxide films in this *** etch rate of the silicon films significantly increases while the silicon oxide is slightly etched with the gas pressures and *** was also found that the etch rate strongly depends on the wafer position on the processing chamber electrode,and that the etch selectivity reached 96-131 in the d.s.harge conditions of RF powers (3730-4180 W) and gas pressures (3.6-4 Torr).

关键词： remote plasma source electron density cutoff probe downstream etch

Regulation of sleep by astrocytes in the hypothalamic ventrolateral preoptic nucleus

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Neural Regeneration Research 2025年第4期20卷 1098-1100页

作者： Jae-Hong Kim Ruqayya Afridi Il-sung Jang Maan Gee lee Kyoungho suk Brain Korea 21 four KNU Convergence Educational Program of Biomedical sciences for Creative Future Talents School of MedicineKyungpook National UniversityDaeguRepublic of Korea department of Pharmacology School of MedicineKyungpook National UniversityDaeguRepublic of Korea department of Pharmacology School of DentistryKyungpook National UniversityDaeguRepublic of Korea Brain science&Engineering Institute Kyungpook National UniversityDaeguRepublic of Korea

Astrocytes are functionally dynamic cells that support neurons in multiple ways throughout an organism’s *** astrocytic regulation of neuronal activity has been increasingly recognized in recent *** are now recognized as playing a more complex role than mere bystanders in the central nervous ***,their role in regulating the sleep neurocircuitry is not well *** this perspective,we highlight the role of astrocytes in sleep modulation,with a particular focus on regulatory mechanisms related to the ventrolateral preoptic nucleus(VLPO)of the *** briefly d.s.uss recent literature reporting the role of VLPO astrocytes in regulating sleep-associated behaviors.

关键词： sleep ventrolateral astrocytes

Chlorophyll, anthocyanin, and gas exchange changes assessed by spectroradiometry in Fragaria chiloensis under salt stress

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Journal of Integrative Plant Biology 2014年第5期56卷 505-515页

作者： Miguel Garriga Jorge B. Retamales sebastián Romero-Bravo Peter d.s. Caligari Gustavo A. Lobos Faculty of Agricultural sciences Plant Breeding and Phenomic Center Universidad de Talca Instituto de Biología Vegetaly Biotecnología Universidad de Talca

Chlorophyll and anthocyanin contents provide a valuable indicator of the status of a plant’s physiology, but to be more widely utilized it needs to be assessed easily and non‐d.s.ructively. This is particularly evident in terms of assessing and exploiting germplasm for plant‐breeding programs. We report, for the first time, experiments with Fragaria chiloensis（L.）duch. and the estimation of the effects of response to salinity stress（0, 30, and 60 mmol NaCl/L） in terms of these pigments content and gas exchange. It is shown that both pigments（which interestingly, themselves show a high correlation） give a good indication of stress response. Both pigments can be accurately predicted using spectral reflectance indices（sRI）;however, the accuracy of the predictions was slightly improved using multilinear regression analysis models and genetic algorithm analysis. specifically for chlorophyll content, unlike other species, the use of published.s.I gave better indications ofstress response than Normalized difference Vegetation *** effect of salt on gas exchange is only evident at the highest concentration and.s.me sRI gave better prediction performance than the known Photochemical Reflectance Index. This information will therefore be useful for identifying tolerant genotypes to salt stress for incorporation in breeding programs.

关键词： Gas exchange high‐throughput phenotyping pigment phenomic photosynthesis reflectance spectral reflectance indices

Refining constitutive relation by integration of finite element simulations and Gleeble experiments

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Journal of Materials science & Technology 2019年第6期35卷 1039-1043页

作者： d.J. Yu d.s. Xu H. W ang Z.B. Zhao G.Z. Wei R. Yang College of sciences Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Thermo-mechanical coupled finite element calculations were carried out to simulate the Gleeble compression of the samples of a titanium alloy(Ti60), and the results are analyzed and compared with the actual compression tests conducted on a Gleeble 3800 thermo-mechanical simulator. The changes in temperature, stress and.s.rain d.s.ribution in the samples and the source of error on the constitutive relations from Gleeble hot compression test were analyzed in detail. Both simulations and experiments showed that the temperature d.s.ribution in the specimen is not uniform during hot compression, resulting in significant deformation inhomogeneity and non-ignorable error in the flow stress strain relation,invalidating the uniform strain assumption commonly assumed when extracting the constitutive relation from Gleeble tests. Based on the finite element simulations with iterative corrections, we propose a scheme to refine the constitutive relations from Gleeble tests.

关键词： Titanium alloy Constitutive relation Finite element Compression Temperature d.s.ribution

Anti-amyloid antibodies in Alzheimer’s d.s.ase: what did clinical trials teach us?

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Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s d.s.ase(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in d.s.ase onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.smith Liwen Zhou Cameron L.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne Allgood Jared.s.Bushman George d.Bittner department of Molecular Biosciences University of Texas at AustinAustinTXUSA department of Neuroscience University of Texas at AustinAustinTXUSA division of Pharmaceutical sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred.s.rague–dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration

Revisiting cerebral endothelial cells in Alzheimer’s d.s.ase

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s d.s.ase(Ad)is the most common neurodegenerative d.s.rder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,Ad is familial,as often pred.s.osed by genetic mutations(Hoogmartens et al.,2021),while sporadic Ad accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain Ad pathogenesis as d.s.egulated homeostasis of amyloid-β(Aβ)peptid.s.that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of Ad.

关键词： Alzheimer Aβ cerebral