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VISCOELASTIC BEHAVIOR OF THE NON-HOOKE DEFORMATION BEFORE YIELDING IN UNIAXIAL DRAWING OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)

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Chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： zhen-hua yuan De-yan Shen Ren-yuan Qian Polymer Physics Laboratory Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Chinese Acad Sci Inst Chem Ctr Mol Sci Polymer Phys Lab Beijing 100080 Peoples R China

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu Tang zhen-hua Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHB model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Multiple Melting Endotherms of Syndiotactic Polystyrene in β Crystalline Form

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Chinese Chemical Letters 2000年第4期11卷 367-368页

作者： zhen hua yuan De Yan SHEN (Polymer Physics Laboratory, Center for Molecular Science. Institute of Chemistry. Chinese Academy of Sciences, Beijing 100080) Chinese Acad Sci Inst Chem Ctr Mol Sci Polymer Phys Lab Beijing 100080 Peoples R China

A series of syndiotactic polystyrene (SPS) samples in β crystalline form were prepared by cooling from the melt at various cooling rates. The effects of cooling rate from the melt, and DSC heating rate on the multiple melting behaviors of β crystals were investigated by differential scanning calorimetry (DSC) and modulated differential scanning calorimetry (MDSC), from which the *** the multiple melting behavior was ascribed to the occurring of a recrystallization process.

关键词： Multiple melting behavior syndiotactic polystyrene recrystalliation.

Deep genome skimming reveals the hybrid origin of Pseudosasa gracilis (Poaceae: Bambusoideae)

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Plant Diversity 2024年第3期46卷 344-352页

作者： Xiang-Zhou Hu Cen Guo Sheng-yuan Qin De-Zhu Li zhen-hua Guo Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Pseudosasa gracilis(Poaceae:Bambusoideae)is a temperate woody bamboo species endemic to Southcentral China with a narrow *** phylogenetic studies revealed an unexpected,isolated phylogenetic position of *** we conducted phylogenomic analysis by sampling populations of *** and its sympatric species *** and Sinosasa polytricha reflecting different genomic signals,by deep genome *** molecular evidence from chloroplast genes and genome-wide SNPs,we deciphered the phylogenetic relationships of *** plastid and nuclear data indicate that *** is more closely related to Sinosasa,which is discordant with the taxonomic *** further explore this molecular-morphological conflict,we screened 411“perfect-copy”syntenic genes to reconstruct phylogenies using both the concatenation and coalescent *** observed extensive discordance between gene trees and the putative species tree.A significant hybridization event was detected based on 411 genes from the D subgenome,showing *** was a hybrid descendant between Sinosasa longiligulata and ***,with 63.56%and 36.44%inheritance probabilities of each ***,introgression events were detected in the C subgenome between *** and *** in the same distribution *** findings suggest that sympatric hybridization and introgression play a crucial role in the origin of *** providing an empirical example of bamboo of hybrid origin using comprehensive analyses based on genomic data from different inheritance systems and morphological characters,our study represents a step forward in understanding of reticulate evolution of bamboos.

关键词： Phylogenomics Hybridization Introgression Pseudosasa gracilis Pseudosasa Sinosasa

Novel ATL1 mutation in a Chinese family with hereditary spastic paraplegia: A case report and review of literature

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World Journal of Clinical Cases 2019年第11期7卷 1358-1366页

作者： Xue-Wen Xiao Juan Du Bin Jiao Xin-Xin Liao Lu Zhou Xi-Xi Liu zhen-hua yuan Li-Na Guo Xin Wang Lu Shen Zhang-yuan Lin Department of Neurology Xiangya Hospital Central South University Changsha 410008 Hunan Province China National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha 410008 Hunan Province China Key Laboratory of Hunan Province in Neurodegenerative Disorders Central South University Changsha 410008 Hunan Province China Department of Geriatrics Neurology Xiangya Hospital Central South University Changsha 410008 Hunan Province China Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan Province Changsha 410008 Hunan Province China Department of Orthopedics Xiangya Hospital Central South University Changsha 410008 Hunan Province China

BACKGROUND Hereditary spastic paraplegias (HSPs) refer to a group of heterogeneous neurodegenerative diseases characterized by lower limbs spasticity and weakness. So far, over 72 genes have been found to cause HSP (SPG1-SPG72). Among autosomal dominant HSP patients, spastic paraplegia 4 (SPG4/SPAST) gene is the most common pathogenic gene, and atlastin-1 (ATL1) is the second most common one. Here we reported a novel ATL1 mutation in a Chinese spastic paraplegia 3A (SPG3A) family, which expands the clinical and genetic spectrum of ATL1 mutations. CASE SUMMARY A 9-year-old boy with progressive spastic paraplegia accompanied by right hearing loss and mental retardation for five years was admitted to our *** history was unremarkable. The family history was positive, and his grandfather and mother had similar symptoms. Neurological examinations revealed hypermyotonia in his lower limbs, hyperreflexia in knee reflex, bilateral positive Babinski signs and scissors gait. The results of blood routine test, liver function test, blood glucose test, ceruloplasmin test and vitamin test were all normal. The serum lactic acid level was significantly increased. The testing for brainstem auditory evoked potential demonstrated that the right side hearing was impaired while the left was normal. Magnetic resonance imaging showed mild atrophy of the spinal cord. The gene panel test revealed that the proband carried an ATL1 c.752A>G ***251Arg (p.Q251R) mutation, and Sanger sequencing confirmed the existence of family co-segregation. CONCLUSION We reported a novel ATL1 Q251R mutation and a novel clinical phenotype of hearing loss in a Chinese SPG3A family.

关键词： Hereditary spastic paraplegia SPG3A Atlastin-1 (ATL1) gene Hearing loss Case report

Loss of heterozygosity for chromosomes 16q in Wilms tumors predicts outcomes:A meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2159-2167页

作者： yuan-hua Song Wen-Ling Li zhen Yang Yan Gao Zhi-Ping Feng Department of Oncology Kunming Children's HospitalKunming 650103Yunnan ProvinceChina Department of Nuclear Medicine The Third Affiliated Hospital of Kunming Medical University(Yunnan Cancer Hospital)Kunming 650118Yunnan ProvinceChina

BACKGROUND The research findings suggest that the prognosis of children with Wilms tumor(WT)is affected by various *** scholars have indicated that loss of heterozygosity(LOH)on chromosome 16q is associated with a poor prognosis in patients with *** To further elucidate this relationship,we conducted a *** This meta-analysis was registered in INPLASY(INPLASY2023100060).We systematically searched databases including Embase,PubMed,Web of Science,Cochrane,and Google Scholar up to May 31,2020,for randomized trials reporting any intrapartum fetal surveillance *** meta-analysis was performed within a frequentist framework,and the quality and network inconsistency of trials were *** ratios and 95%CIs were calculated to report the relationship between event-free survival and 16q LOH in patients with *** Eleven cohort studies were included in this meta-analysis to estimate the relationship between event-free survival and 16q LOH in patients with WT(I^(2)=25%,P<0.001).As expected,16q LOH can serve as an effective predictor of eventfree survival in patients with WT(risk ratio=1.95,95%CI:1.52–2.49,P<0.001).CONCLUSION In pediatric patients with WT,there exists a partial correlation between 16q LOH and an unfavorable treatment *** detection of 16q chromosome LOH warrants increased attention to the patient’s prognosis.

关键词： Loss of heterozygosity Wilms tumor Survival time Chromosomes 16q

Mechanism of high-energy pulsed current-assisted rolling of 08AL carbon steel ultra-thin strip

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Journal of Iron and Steel Research International 2024年第2期31卷 416-427页

作者： Zhong-kai Ren Ya-nan Xu Jia-zhao Chen He Li Rui-lin yuan zhen-hua Wang Tao Wang Xiao Liu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710016ShaanxiChina

To improve the plastic deformation performance of a 08AL carbon steel ultra-thin strip,a pulsed electric field was integrated into the plastic processing of the ultra-thin strip,and the effects of high-energy current on its deformation ability were ***-assisted tensile tests were employed,and the results clarified that the pulsed current could reduce the activation energy of faults and promoted dislocation slip within grains and at grain boundaries,leading to a decrease in the deformation resistance of the metal and an increase in its plastic *** the current density of 2.0 A/mm2,the yield strength,tensile strength,and elongation of the rolled sample reached 425 MPa,467 MPa,and 12.5%,*** the rolling process,it was found that the pulsed current promoted the dynamic recrystallization of the ultra-thin strip,reduced its dislocation density and deformation resistance,and promoted the coordinated deformation of the metal.

关键词： 08AL ultra-thin strip High-energy pulsed current Mechanical property Dislocation density Dynamic recrystallization

Anti-saturation fault-tolerant adaptive torsional vibration control with fixed-time prescribed performance for rolling mill main drive system

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Journal of Iron and Steel Research International 2024年第3期31卷 660-669页

作者： Shuang Liu Chen Du Cong Zhang zhen-hua Bai Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter ***,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the ***,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter *** on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation *** to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric ***,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

关键词： Fixed-time prescribed performance Control input saturation Actuator fault Unknown time-varying gain Adaptive control Asymmetric constraint

Revisiting the island of hexadecapoledeformation nuclei in the A≈150 mass region:focusing on the model application to nuclear shapes and masses

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Communications in Theoretical Physics 2024年第2期76卷 74-88页

作者： Xiao-Yang Wei hua-Lei Wang zhen-zhen Zhang Min-Liang Liu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Based on the potential-energy-surface calculation,the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around^(152)Nd,located on one of the hexadecapole-deformation islands,is analyzed in a multi-dimensional deformation *** energy maps,curves and tables are presented to indicate nuclear *** calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other *** is found that the inclusion of the hexadecapole deformations,especially the axial one,can improve the theoretical description of both nuclear shapes and *** addition,our calculated potential-energy curve shows that a critical deformation-point,β_(2)≈0.4,exists—the triaxial(hexadecapole)deformation effect can be neglectable but the hexadecapole(triaxial)one plays an important role before(after)such a critical point.

关键词： hexadecapole deformation binding energy potential-energy-surface calculation nuclear property