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Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as elucidated by Solid-State NMR

Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen Zi-Shuo Wu ya.Hui Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

the chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(teG-eH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(e_a=20.2 kJ/mol) as compared with that of the pristine one(e_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISe NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.this is further supported by torchia's t_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

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energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang Gao ya.qiang Li Dan Liu Guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and ecological engineering University of Science and Technology BeijingBeijing100083China

energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology energy saving techno-economic model Investment cost

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Plume-lithosphere interaction in the Comei Large Igneous Province: evidence from two types of mafic dykes in Gya.gze, south tibet, China

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China Geology 2024年第1期7卷 80-90页

作者： ya.ying Wang Ling-sen Zeng Li-e Gao Li-long ya. Ling-hao Zhao Jia-hao Gao Ying-long Di Guang-xu Li Yi-hong tian Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China China Nonferrous Metals(Guilin)Geology and Mining Co. LtdGuilin 541004China

two suites of mafic dykes,t1193-A and t1194-A,outcrop in Gya.gze area,southeast *** are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gya.gze,t0902 dyke with 137.7±1.3 Ma zircon age and t0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation *** all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be ***“OIB-type”samples,including t1193-A and t0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle ***“weak enriched-type”samples,including t1194-A and t0902 dykes,have Rees and trace element patterns showing withinplate affinity but have obvious Nb-ta-ti negative *** show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle *** their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in tethya. Himalaya.these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient tethya. Himalaya.subcontinental lithospheric mantle(SCLM)in different *** weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere *** process may lead to strong modification of the tethya. Himalaya.lithosphere in the early Cretaceous.

关键词： OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-ta-ti negative anomaly Kerguelen plume Geological survey engineering tibet Plateau

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Astrophysical S-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： S.B.Dubovichenko A.S.tkachenko R.ya.Kezerashvili N.A.Burkova B.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of technology City University of New YorkBrooklyn11201 New YorkUSA Graduate School and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)S_(1) resonances due to e1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy S-factor,and the extrapolated S(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances is elucidated.A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).the reaction rate enhancement due to the cascade transitions is observed from t_(9)>0.3 and reaches the maximum factor~1.3 at t_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

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ρ-meson longitudinal leading-twist distribution amplitude revisited and the D→ρsemileptonic decay

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Chinese Physics C 2024年第6期48卷 82-91页

作者：钟涛代亚红付海冰 Department of Physics Guizhou Minzu UniversityGuiyang 550025China

Motivated by our previous study[***.D 104(1),016021(2021)]on the pionic leading-twist distribution amplitude(DA),we revisit theρ-me son leading-twist longitudinal DAφ_(2;ρ)^(‖)(x,μ)in this study.A model proposed by Chang based on the DYyson-Schwinger equations is adopted to describe the behavior ofφ_(2;ρ)^(‖)(x,μ).However,theξ-moments ofφ_(2;ρ)^(‖)(x,μ)are calculated with the QCD sum rules in the framework of the background field *** sum rule formulas for these moments are *** accurate values for the first five nonzeroξ-moments at the typical scaleμ=(1.0,1.4,2.0,3.0)GeV are given,e.g.,atμ=1 GeV,(ξ^(2))>_(2;ρ)^(‖)=0.220(6),(ξ^(4))>_(2;ρ)^(‖)=0.103(4),(ξ^(6))>_(2;ρ)^(‖)=0.066(5),(ξ^(8))>_(2;ρ)^(‖)=0.046(4),and(ξ^(10))>_(2;ρ)^(‖)=0.035(3).By fitting these values with the least squares method,the DSe model forφ_(2;ρ)(x,μ)is *** taking the left-handed current light-cone sum rule approach,we obtain the transition form factor in the large recoil region,i.e.,A_(1)(0)=0.498_(-0.012)^(+0.014),A_(2)(0)=0.460_(-0.047)^(+0.055),and V(0)=0.800_(-0.014)^(+0.015),and the ratio r_(2)=0.923_(-0.119)^(+0.133),rV=1.607_(-0.071)^(+0.071).After extrapolating with a rapidly converging series based on z(t)-expansion,we present the|V_(cd)|-independent decay width for the semileptonic decays D→ρ^(l+)v_(l).Finally,the branching fractions are B(D^(0)→ρ^(-)e+v_(e))=1.825_(-0.162)^(+0.170)±0.004,B(D^(+)→ρ^(0)e+v_(e))=2.299_(-0.204)^(+0.214)±0.011,B(D^(0)→ρ^(-)μ^(+)v_(μ))=1.816_(-0.160)^(+0.168)±0.004,and B(D^(+)→ρ^(0)μ+v_(μ))=2.288_(-0.201)^(+0.212)±0.011.

关键词： QCD sum rule charmed meson semileptonic decay Rho meson light-cone distribution amplitude

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Crocus genome reveals the evolutionary origin of crocin biosynthesis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1878-1891页

作者： Zhichao Xu Shanshan Chen ya.in Wang ya.tian Xiaotong Wang tianyi Xin Zishan Li Xin Hua Shengnan tan Wei Sun Xiangdong Pu Hui ya. Ranran Gao Jingyuan Song Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of the People's Republic of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China State Key Laboratory of Basis and New Drug Development of Natural and Nuclear Drugs Engineering Research Center of Chinese Medicine ResourceMinistry of EducationBeijing 100193China College of Life Science Northeast Forestry UniversityHarbin 150040China Key Laboratory of Beijing for Identification and Safety evaluation of Chinese Medicine China Academy of Chinese Medical SciencesInstitute of Chinese Materia MedicaBeijing 100700China Analysis and testing Center of Northeast Forestry University Harbin 150040China School of Pharmacy Anhui Medical UniversityInflammation and Immune Mediated Diseases Laboratory of Anhui ProvinceHefei 230032China

Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, e181, t259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.

关键词： Crocus sativus WGt Crocin biosynthesis Carotenoids Apocarotenoids CCDs

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Hydraulic properties and drought response of a tropical bamboo (Cephalostachyum pergracile)

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Plant Diversity 2024年第3期46卷 406-415页

作者： Wanwalee Kongjarat Lu Han Amy Ny Aina Aritsara Shu-Bin Zhang Gao-Juan Zhao Yong-Jiang Zhang Phisamai Maenpuen Ying-Mei Li Yi-Ke Zou Ming-Yi Li Xue-Nan Li Lian-Bin tao ya.Jun Chen CAS Key Laboratory of tropical Forest ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China University of the Chinese Academy of Sciences Beijing 100049China t-StAR Core team Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China School of Biology and ecology University of MaineOronoMEUSA Climate Change Institute University of MaineOronoME 04469USA School of Biological and Chemical Science Pu’er UniversityXueyuan RoadYunnan 665000China Institute of ecology and Geobotany School of Ecology and Environmental SciencesYunnan UniversityKunmingYunnan 650091China School of ecology and environment Southwest Forestry UniversityKunmingYunnan 650224China Yuanjiang Savanna ecosystem Research Station Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYuanjiangYunnan 653300China

Bamboo plants are an essential component of tropical ecosystems,yet their vulnerability to climate extremes,such as drought,is poorly understood due to limited knowledge of their hydraulic *** pergracile,a commonly used tropical bamboo species,exhibited a substantially higher mortality rate than other co-occurring bamboos during a severe drought event in 2019,but the underlying mechanisms remain *** study investigated the leaf and stem hydraulic traits related to drought responses,including leaf-stem embolism resistance(P50leaf;P50stem) estimated using optical and X-ray microtomography methods,leaf pressure-volume and water-releasing ***,we investigated the seasonal water potentials,native embolism level(PLC) and xylem water source using stable *** found that *** exhibited strong resistance to embolism,showing low P50leaf,P50stem,and turgor loss point,despite its rapid leaf water ***,its leaves displayed greater resistance to embolism than its stem,suggesting a lack of effective hydraulic vulnerability segmentation(HVS) to protect the stem from excessive xylem *** the dry season,approximately 49% of the water was absorbed from the upper 20-cm-deep soil ***,significant diurnal variation in leaf water potentials and an increase in midday PLC from 5.87±2.33% in the wet season to 12.87±4.09%in the dry season were *** summary,this study demonstrated that the rapid leaf water loss,high reliance on surface water,and a lack of effective HVS in *** accelerated water depletion and increased xylem embolism even in the typical dry season,which may explain its high mortality rate during extreme drought events in 2019.

关键词： Climate change Drought Hydraulic safety Hydraulic vulnerability segmentation Stable isotope tree mortality

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Prediction model for hepatitis B e antigen seroconversion in chronic hepatitis B with peginterferon-alfa treated based on a responseguided therapy strategy

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World Journal of Hepatology 2024年第3期16卷 405-417页

作者： Pei-Xin Zhang Xiao-Wei Zheng ya.Fei Zhang Jun Ye Wei Li Qian-Qian tang Jie Zhu Gui-Zhou Zou Zhen-Hua Zhang Department of Infectious Diseases The Second Affiliated Hospital of Anhui Medical UniversityHefei 230601Anhui ProvinceChina Department of Infectious Diseases Anhui Provincial HospitalHefei 230000Anhui ProvinceChina Department of Hepatology The Second People’s Hospital of Fuyang CityFuyang 236000Anhui ProvinceChina

BACKGROUND Models for predicting hepatitis B e antigen(HBeAg)seroconversion in patients with HBeAg-positive chronic hepatitis B(CHB)after nucleos(t)ide analog treatment are *** to establish a simple scoring model based on a response-guided therapy(RGt)strategy for predicting HBeAg seroconversion and hepatitis B surface antigen(HBsAg)*** In this study,75 previously treated patients with HBeAg-positive CHB underwent a 52-week peginterferon-alfa(PeG-IFNα)treatment and a 24-wk *** regression analysis was used to assess parameters at baseline,week 12,and week 24 to predict HBeAg seroconversion at 24 wk *** two best predictors at each time point were used to establish a prediction model for PeG-IFNαtherapy *** at each time point that met the corresponding optimal cutoff thresholds were scored as 1 or *** the two most meaningful predictors were HBsAg≤1000 IU/mL and HBeAg≤3 S/CO at baseline,HBsAg≤600 IU/mL and HBeAg≤3 S/CO at week 12,and HBsAg≤300 IU/mL and HBeAg≤2 S/CO at week *** a total score of 0 vs 2 at baseline,week 12,and week 24,the response rates were 23.8%,15.2%,and 11.1%vs 81.8%,80.0%,and 82.4%,respectively,and the HBsAg clearance rates were 2.4%,3.0%,and 0.0%,vs 54.5%,40.0%,and 41.2%,*** We successfully established a predictive model and diagnosis-treatment process using the RGt strategy to predict HBeAg and HBsAg seroconversion in patients with HBeAg-positive CHB undergoing PeG-IFNαtherapy.

关键词： Chronic hepatitis B Hepatitis B e antigen-positive Peginterferon-alfa Prediction model Response-guided therapy strategy

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电子温度各向异性对螺旋波m=1角向模功率沉积特性的影响

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物理学报 2024年第7期73卷 262-270页

作者：李文秋唐彦娜刘雅琳王刚中国科学院空天信息创新研究院北京100190 中国科学院大学北京100049

采用一般的径向密度非均匀分布假设,借助温等离子体介电张量模型,利用磁化等离子体中电磁波的一般色散关系,在高密度峰值、低磁场、低气压典型参量条件下,重点分析了电子温度各向异性对螺旋波m=1角向模功率沉积特性的影响.研究结果表明... 详细信息

采用一般的径向密度非均匀分布假设,借助温等离子体介电张量模型,利用磁化等离子体中电磁波的一般色散关系,在高密度峰值、低磁场、低气压典型参量条件下,重点分析了电子温度各向异性对螺旋波m=1角向模功率沉积特性的影响.研究结果表明:在典型螺旋波等离子体电子温度范围(3,8)e V内,电子有限拉莫尔半径效应应当予以考虑,而离子有限拉莫尔半径效应可以忽略.低磁场条件下|n|>1次回旋谐波对介电张量元素的贡献可以忽略.碰撞阻尼在功率沉积中占据主导地位,功率沉积在偏离等离子体柱中心轴的某一径向位置出现峰值,随着轴向电子温度t_(e,z)的增大,功率沉积强度逐渐增强.相比等离子体温度各向同性情形,等离子体温度各向异性显著改变了螺旋波m=1角向模的功率沉积特性,电子温度各向异性因子χ=t_(e,⊥)/t_(e,z)的增大或减小均导致功率沉积强度发生剧烈改变.

关键词：螺旋波等离子体各向异性传播特性功率沉积

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Medium effects in ΛK~＋ pair production by 2.83 GeV protons on nuclei

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Chinese Physics C 2017年第12期41卷 88-105页

作者： e. ya. Paryev M. Hartmann Yu. t. Kiselev Institute for Nuclear Research Russian Academy of Sciences Moscow 117312 Russia Institute for theoretical and experimental Physics Moscow 117218 Russia Institut für Kernphysik and Jülich Centre for Hadron Physics Forschungszentrum Jiilich D-52425 Jiilich Germany

We study ΛK~＋ pair production in the interaction of protons of 2.83 GeV kinetic energy with C, Cu,Ag, and Au target nuclei in the framework of the nuclear spectral function approach for incoherent primary proton–nucleon and secondary pion–nucleon production processes, and processes associated with the creation of intermediate Σ~0K~＋ pairs. the approach accounts for the initial proton and final Λ hyperon absorption, final K~＋ meson distortion in nuclei, target nucleon binding, and Fermi motion, as well as nuclear mean-field potential effects on these *** calculate the Λ momentum dependence of the absolute ΛK~＋ yield from the target nuclei considered, in the kinematical conditions of the ANKe experiment, performed at COSY, within the different scenarios for the Λ-nucleus effective scalar potential. We show that the above observable is appreciably sensitive to this potential in the low-momentum region. therefore, direct comparison of the results of our calculations with the data from the ANKe-at-COSY experiment can help to determine the above potential at finite momenta. We also demonstrate that the two-step pion–nucleon production channels dominate in the low-momentum ΛK~＋ production in the chosen kinematics and, therefore, they have to be taken into account in the analysis of these data.

关键词： proton-nucleus reactions medium effects hyperon nuclear potential

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