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Quantitative studies on charcoalification:Physical and chemical changes of charring wood

Fundamental Research 2024年第1期4卷 113-122页

作者： gang Li Linlin gao Fengwen Liu Menghan Qiu Guanghui Dong MOE Key Laboratory of Western China's Environmental Systems College of Earth&Environmental SciencesLanzhou UniversityLanzhou 730000China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environment ScienceYunnan UniversityKunming 650504China

Charcoal is commonly preserved in both natural and artificial sediments,and is intensively used in paleontological,paleoenvironmental,and archaeological studies due to the abundant bio-information it *** biochemical properties of charcoal are also used for paleoclimatic reconstruction;however,the reliability of this approach has been challenged due to a lack of clarity on how physicochemical properties change during the charring process,as well as the temperatures required for *** address this lack,in this study,Qinghai spruce and Chinese pine wood samples from the northeastern Tibetan Plateau were heated at different temperatures and for different lengths of time under restricted oxygen *** reflectance;carbon,nitrogen,and oxygen content;and tracheid morphology were quantified before and after heating to assess changes related to the charring *** charcoal remains were then evaluated to determine the charcoalification temperatures by comparing with the experimental *** minimum temperature required for wood charcoalification was∼300℃,while temperatures recorded by archaeological charcoal were concentrated at 400-500℃.During the charring experiments,the tracheid cell walls gradually homogenized,and tracheid cell wall thickness and lumen area decreased by∼20%.On average,50%mass losses were observed;the carbon and oxygen content(%wt.)approximately changed from 47%to 60%and 48%to 35%respectively,while the nitrogen content(%wt.)fluctuated around 0.2%.The reflectance increased slightly from 0%to 0.5%.We propose that the charcoalification of wood tissue refers to charring(in restricted air)and carbonization(in the almost absence of air)when the wood is exposed to a heat source,which then finally transforms into a black,inert *** quantitative study provided valuable data and a thorough assessment of the process of wood charcoalification,as well as accurately estimated the feasibility of using charcoal phys

关键词： Charcoalification Quantitative study Charcoal formation Archaeological charcoal Tracheid cell wall thickness Reflectance

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Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-Dong Zhang Dong-Ting gao gang Liu Chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

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A novel videogrammetry-based full-field dynamic deformation monitoring method for variable-sweep wings

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Acta Mechanica Sinica 2024年第8期40卷 120-132页

作者： Liqiang gao Yan Liu Bin Jiang Zhendong Ge Haoyang Li Xiang Guo Tao suo Qifeng Yu School of Civil Aviation Northwestern Polytechnical UniversityXi’an710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Application Northwestern Polytechnical UniversityXi’an710072China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China Institute of Intelligent Optical Measurement and Detection Shenzhen UniversityShenzhen518060China

The measurement of wing dynamic deformation in morphing aircraft is crucial for achieving closed-loop control and evaluating structural *** variable-sweep wings with active large deformation,this paper proposes a novel videogrammetric method for full-field dynamic deformation measurement.A stereo matching method based on epipolar geometry constraint and topological constraint is presented to find the corresponding targets between stereo *** addition,a new method based on affine transformation combined with adjacent closest point matching is developed,aiming to achieve fast and automatic tracking of targets in time-series images with large deformation.A calculation model for dynamic deformation parameters is established to obtain the displacement,sweep variable angle,and span *** verify the proposed method,a dynamic deformation measurement experiment is conducted on a variable-sweep wing *** results indicate that the actual accuracy of the proposed method is approximately 0.02%of the measured area(e.g.,0.32 mm in a 1.6 m scale).During one morphing course,the sweep variable angle,the span variation and the displacement increase gradually,and then *** maximum sweep variable angle is 36.6°,and the span variation is up to 101.13 *** overall configuration of the wing surface is effectively reconstructed under different morphing states.

关键词： Morphing aircraft Variable-sweep wing Videogrammetry Large dynamic deformation Target matching and tracking

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Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： Zhi-gang Chen gao-Qin Liu Wei-Ming Liu Pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability

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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

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Plant Diversity 2024年第3期46卷 353-361页

作者： Jingya Zhang Cui Xiao Xiaoyu Duan Xin gao Hao Zeng Rong'an Dong gang Feng Keping Ma Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection *** study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory *** Forest models were then used to find the most parsimonious multivariate *** results showed that interannual variation in specimen number between 1900 and 2020 was *** number of these species in southeast China was notably lower than that in northwest *** range and geographical range of species had significant positive correlations with specimen *** addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal *** findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting *** correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

关键词： Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits

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Clinicopathological characteristics and typing of multilocular cystic renal neoplasm of low malignant potential

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World Journal of Clinical Cases 2024年第14期12卷 2332-2341页

作者： Wen-Long gao gang Li Dong-Sheng Zhu Yuan-Jie Niu Department of Urology The Second Hospital of Tianjin Medical UniversityTianjin 300211China Department of Pediatric Surgery The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Up until now,no research has been reported on the association between the cli-nical growth rate of multilocular cystic renal neoplasm of low malignant potential(MCRNLMP)and computed tomography(CT)imaging *** study sought to examine the correlation between them,with the objective of distin-guishing unique features of MCRNLMP from renal cysts and exploring effective management *** To investigate optimal management strategies of *** We retrospectively collected and analyzed data from 1520 patients,comprising 1444 with renal cysts and 76 with MCRNLMP,who underwent renal cyst decom-pression,radical nephrectomy,or nephron-sparing surgery for renal cystic disease between January 2013 and December 2021 at our *** of MC-RNLMP utilized the Bosniak classification for imaging and the 2016 World Health Organization criteria for clinical *** Our meticulous exploration has revealed compelling findings on the occurrence of ***,it comprises 1.48%of all cases involving simple renal cysts,5.26%of those with complex renal cysts,and a noteworthy 12.11%of renal tumors coexisting with renal cysts,indicating a statistically significant difference(P=0.001).Moreover,MCRNLMP constituted a significant 22.37%of the patient po-pulation whose cysts demonstrated a rapid growth rate of≥2.0 cm/year,whereas it only represented 0.66%among those with a growth rate below 2.0 cm/*** the 76 MCRNLMP cases studied,none of the nine patients who underwent subsequent nephron-sparing surgery or radical nephrectomy following renal cyst decompression experienced recurrence or *** the remaining 67 patients,who were actively monitored over a 3-year postoperative period,only one showed suspicious recurrence on CT *** MCRNLMP can be tentatively identified and categorized into three types based on CT scanning and growth rate *** treating MCRNLMP,partial nephrectomy is preferred,while rad

关键词： Renal cysts Multilocular cystic renal neoplasm of low malignant potential Computed tomography Diagnosis Treatment

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Ginsenoside Rg3 Promotes the Survival and Migration of Trophoblast Cells in a Rat Model of Gestational Hypertension by Regulating miR-100a/Insulin Growth Factor-2 Axis

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 65-74页

作者： Xiu-Mei Fan Li Yang gang Zhao Sen-Ye Huo Yan gao Department of Obstetrics Xingtai Third HospitalXingtaiChina Department of Obstetrics Xingtai Maternal and Child Health Care HospitalXingtaiChina

Objective:Preeclampsia(PE)is a common complication during ***-100a is expressed in the placenta and regulates the survival and development of placental *** growth factor-2(IGF-2)may serve as its downstream *** study investigated the protective mechanisms of ginsenoside Rg3 against PE in rat *** and Methods:LPS-induced rat PE models were suitable for intravenous administration of the highly expressed miR-100a ginsenoside Rg3 lentiviral *** trophoblasts were cultured in vitro for JEG-3,and PE cell models were *** vivo effects on tumor growth and apoptosis were *** Rg3 was treated with different concentrations of shRNA,miR-100a analogs,inhibitors,or *** and the expression of autophagy-related proteins were *** activity and migration were determined using Cell Counting Kit-8 and Transwell *** drugs strongly inhibited trophoblasts under normal conditions with some synergy between ***-luciferase return assay confirmed the binding affinity of miR-100a for ***:In response to Rg3,autophagy and the expression of autophagy-related proteins LC3-I/II,Beclin1,and SQSTM1 were reduced in PE rat placental ***3 inhibited autophagy in JEG-3 cells and promoted JEG-3 survival and migration in a concentration-dependent ***-100a upregulated PE *** results suggested that autophagy was a vital signaling ***3 intervention inhibited miR-100a expression and miR-100a downregulated IGF-2 expression in placental tissues and promoted autophagy,thereby inhibiting JEG-3cell survival and *** rats,Rg3 inhibited PE development by regulating the activity of the miR-100a-IGF-2 signaling ***:Ginsenoside Rg3 positively regulates the miR-100a-IGF-2 axis and protects PE rats by inhibiting trophoblastic autophagy and promoting trophoblastic cell survival and migration.

关键词： Ginsenoside Rg3 inflammatory response miR-100a/insulin growth factor-2 axis preeclampsia pregnancy-induced hypertension

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Review of Sc microalloying effects in Al-Cu alloys

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1098-1114页

作者： Shenghua Wu Chong Yang Peng Zhang Hang Xue Yihan gao Yuqing Wang Ruihong Wang Jinyu Zhang gang Liu Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Aerospace Engineering North University of ChinaTaiyuan 030051China

Artificially controlling the solid-state precipitation in aluminum (Al) alloys is an efficient way to achieve well-performed properties,and the microalloying strategy is the most frequently adopted method for such a *** this paper,recent advances in lengthscale-dependent scandium (Sc) microalloying effects in Al-Cu model alloys are *** coarse-grained Al-Cu alloys,the Sc-aided Cu/Sc/vacancies complexes that act as heterogeneous nuclei and Sc segregation at the θ′-Al_(2)Cu/matrix interface that reduces interfacial energy contribute significantly to θ′*** grain size refinement to the fine/ultrafine-grained scale,the strongly bonded Cu/Sc/vacancies complexes inhibit Cu and vacancy diffusing toward grain boundaries,promoting the desired intragranular θ′*** nanocrystalline scale,the applied high strain producing high-density vacancies results in the formation of a large quantity of (Cu Sc,vacancy)-rich atomic complexes with high thermal stability,outstandingly improving the strength/ductility synergy and preventing the intractable low-temperature *** review recommends the use of microalloying technology to modify the precipitation behaviors toward better combined mechanical properties and thermal stability in Al alloys.

关键词： aluminum alloy microalloying effect length-scale dependence precipitation mechanical properties

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： Wen-Long Dang gang gao Xin-Cai You Ke-Ting Fan Jun Wu De-Wen Lei Wen-Jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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Introduction of rare-earth element Sc in alloy design to modify wear features of dual-phase high-entropy alloy

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Rare Metals 2024年第2期43卷 817-828页

作者： Hao Ren Rui-Run Chen Xue-Feng gao Tong Liu gang Qin Yu-Lung Chiu Shi-Ping Wu Jing-Jie Guo Guo National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin150001China School of Metallurgy and Materials University of BirminghamBirminghamB152TTUK

Tailoring the alloy composition,which induces the hard secondary phase to increase hardness and strength to improve the wear features,is a feasible approach for developing wear-resistant metal ***,a group of(AlCoCrFeNi)_(100–x)Sc_(x)(x=0–2.0,at%)high-entropy alloys(HEAs)are designed and the phase compositions and wear behaviors are ***-doped HEA series contain the primary body-centered cubic(BCC)and eutectic phases,in which the eutectic phase is composed of the alternately grown BCC and Laves *** addition promotes the diffusion of Ni atoms from BCC phase to form the Sc-rich Laves phase at the grain *** hardness increases due to solid solution strengthening and second phase *** the second phase strengthening plays a more significant role relative to solid solution *** phase and the oxides caused by wear heating prevent the direct contact between friction pair and HEAs,thus inducing a decreased wear rate from 6.82×10^(−5) to 3.47×10^(−5)m^(3)·N^(−1)·m^(−1).Moreover,the wear mechanism changes from adhesive wear,abrasive wear and oxidative wear to abrasive wear and oxidative wear.

关键词： High entropy alloy(HEA) Laves phase Hardness Wear mechanism

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