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Chinese Journal of Polymer Science 2019年第9期37卷 936-942页

作者： Jing Li Kang-Da Wu Huang Shan Jing-Han Zhang Ming Zhao guang-bi gong Wen-Li Guo Yi-Bo Wu College of Materials Science & Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Lanzhou Petrochemical Research Center Petrochina Lanzhou 730060 China Beijing Key Laboratory of Specialty Elastomer Composite Materials Beijing Institute of Petrochemical Technology Beijing 102617 China

The low-activity cationic monomer tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane was synthesized by Grignard reaction and hydroxyl-protection reaction. Living polyisobutylene chains were initially synthesized by controlled cationic polymerization and then capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane. The hydrolysis of these polyisobutylenes end capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane gave rise to hydroxytelechelic polyisobutylene. NMR analysis confirmed that the hydrolysis was complete. Results also showed that a low polymerization temperature favored the participation of tert-butyl-dimethyl-(4- methyl-pent-4?enyloxy)-silane in the end-capping reaction. Moreover, polyisobutylene-based polyurethane exhibited greater acid resistance than commercial polyurethane.

关键词： Carbocationic polymerization Polyisobutylene Hydrolysis Polyisobutylene-based polyurethane

Crevice corrosion of reinforcing steel in carbonated simulated concrete pore solutions contaminated by chloride

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Journal of Iron and Steel Research International 2025年第1期32卷 293-311页

作者： Peng-peng Wu Yuan-pei gong Shao-hua Zhang Yue-zhong Zhang Bao-sheng Liu guang-ling Song College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen518055GuangdongChina School of Mechanical and Mining Engineering Centre for Advanced Materials Processing and Manufacturing(AMPAM)The University of QueenslandSt LuciaQLD4072Australia State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen361005FujianChina

The crevice corrosion of the reinforcing steel in the carbonated simulated concrete pore solutions(SCPSs)containing 0.04 mol/L chloride was *** comparison,the steel without crevice covered on its surface was also *** showed that the crevice corrosion in the uncarbonated SCPS was not triggered and the steel remained passivity by suppressing the anodic dissolution in the crevice *** SCPS was carbonated to have pH values of 10.5 and 11.5,the crevice corrosion was easier to be activated than the widely reported pitting corrosion owing to the rapid oxygen depletion within the crevice,but the crevice corrosion damage might be alleviated to a certain extent due to the relative compact surface film formed inside the *** further carbonation led to the activation dissolution of both the crevice interior and exterior,causing the more serious corrosion *** process of the crevice corrosion was systematically analyzed by combining the electrochemical measurement results and Evens polarization diagram.

关键词： Crevice corrosion Reinforcing steel Carbonation Electrochemical test Rust Evens polarization diagram

Impact of Hard Segment Structures on Fatigue Threshold of Casti

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Chinese Journal of Polymer Science 2025年第2期43卷 303-315页

作者： guang-Zhi Jin Le-Hang Chen Yu-Zhen gong Peng Li Run-Guo Wang Fan-Zhu Li Yong-Lai Lu State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Engineering Research Center of Elastomer Materials Energy Conservation and Resources Ministry of EducationBeijing100029China Key Laboratory of Carbon Fiber and Functional polymers Beijing University of Chemical TechnologyBeijing100029China Center of Advanced Elastomer Materials College of Material Science and EngineeringBeijing University of Chemical TechnologyBeijing100029China

The fatigue resistance of casting polyurethane(CPU)is crucial in various sectors,such as construction,healthcare,and the automotive *** its importance,no studies have reported on the fatigue threshold of *** study employed an advanced Intrinsic Strength Analyzer(ISA)to evaluate the fatigue threshold of CPUs,systematically exploring the effects of three types of isocyanates(PPDI,NDI,TDI)that contribute to hard segment structures based on the cutting *** multiple advanced characterization techniques(XRD,TEM,DSC,AFM),the results indicate that PPDI-based polyurethane exhibits the highest fatigue threshold(182.89 J/m^(2))due to a highest phase separation and a densely packed spherulitic structure,although the hydrogen bonding degree is the lowest(48.3%).Conversely,NDI-based polyurethane,despite having the high hydrogen bonding degree(53.6%),exhibits moderate fatigue performance(122.52 J/m^(2)),likely due to a more scattered ***-based polyurethane,with the highest hydrogen bonding degree(59.1%)but absence of spherulitic structure,shows the lowest fatigue threshold(46.43 J/m^(2)).Compared to common rubbers(NR,NBR,EPDM,BR),the superior fatigue performance of CPU is attributed to its well-organized microstructure,polyurethane possesses a higher fatigue threshold due to its high phase separation degree and orderly and dense spherulitic structure which enhances energy dissipation and reduces crack propagation.

关键词： Casting polyurethane Fatigue threshold Cutting method Hard segment structures Materials characterization

Green revolution gene drives adaptation of Arabidopsis to the extremely high altitude

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Science China Life Sciences 2025年第03期 859-870页

作者： Xing-Hui Hou Yong-Chao Xu Tian-Shu Sun Yan-Bo gong Xin-Tong Li guang-Teng Jin Yu-Tao bian Yi-Ni Liu Juan Jiang Xiao-Min Niu Hong-Ya Gu Ya-Long Guo State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences China National Botanical Garden State Key Laboratory for Protein and Plant Gene Research School of Life Sciences Peking University College of Life Sciences University of Chinese Academy of Sciences

To elucidate the process of adaptation, particularly the traits subject to natural selection and the molecular mechanisms underlying their natural variation, is one of the primary objectives of evolutionary biology. The uplifted landscape offers an excellent framework for understanding how organisms adapt to dramatic climatic gradients. To investigate the genetic basis of plant adaptation to the extremely high altitude, we first compared the genomic and phenotypic variations of two closely related Arabidopsis thaliana accessions from high altitude(Xizang, also known as “Tibet”) and low altitude(Yunnan), respectively. The Xizang population represents a relict group characterized by a small effective population size. Notably, the Xizang genome has more transposable elements(TEs) and more gene loss-offunction(LoF) mutations. Differentially expressed genes were enriched in biological processes of cellular response to oxygen-containing compound, regulation of defense response, and response to light intensity. Intriguingly, the phenotypic selection analysis revealed that silique density was under natural selection. Furthermore, we genetically mapped and validated that the LoF mutation of GA20ox1, the homologous gene of green revolution in rice, resulted in a higher silique density in Xizang Arabidopsis. Given that GA20ox1 is linked to Arabidopsis adaptation to the Alps Mountains, its parallel evolution plays an important role in the adaptation to Alpine habitats. Overall,our results highlight that identifying adaptive traits and elucidating the molecular mechanisms underlying natural variation of these traits is crucial for unraveling the mystery of adaptive evolution and has significant implications for crop breeding.

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Blocking the PD-1 signal transduction by occupying the phosphorylated ITSM recognition site of SHP-2

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Science China(Life Sciences) 2025年第1期68卷 189-203页

作者： Wenjie Li Wenyi Mei Hewei Jiang Jie Wang Xiaoli Li Lina Quan Yanyan Diao Yanni Ma Sisi Fan Zhuwei Xie Mengdie gong Huan Zhu Dewen bi Feng Zhang Lei Ma Jian Zhang Yufeng Gao Aris Paschalidis Honghuang Lin Fangfang Liu Kangdong Liu Mingliang Ye Zhenjiang Zhao Yajun Duan Zhuo Chen Yufang Xu Weilie Xiao Shengce Tao Lili Zhu Honglin Li Shanghai Key Laboratory of New Drug Design School of PharmacyEast China University of Science&TechnologyShanghai 200237China Shanghai Center for Systems biomedicine Key Laboratory of Systems Biomedicine(Ministry of Education)Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationYunnan Characteristic Plant Extraction LaboratoryYunnan Provincial Center for Research&Development of Natural ProductsState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Pharmacy and School of Chemical Science and TechnologyYunnan UniversityKunming650500China CAS Key Laboratory of Separation Sciences for Analytical Chemistry National Chromatographic R&A CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Cardiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China Department of Infectious Diseases The First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Medicine University of Massachusetts Chan Medical SchoolWorcester MA 01655USA Department of Pathophysiology School of Basic Medical SciencesAcademy of Medical ScienceCollege of MedicineZhengzhou UniversityZhengzhou 450001China Innovation Center for AI and Drug Discovery East China Normal UniversityShanghai 200062China Lingang Laboratory Shanghai 200031China

Targeting the PD-1/PD-L1 axis with small-molecular inhibitors is a promising approach for ***,we identify a natural pentacyclic triterpenoid,Pygenic Acid A(PA),as a PD-1 signaling *** exerts anti-tumor activity in hPD-1 knock-in C57BL/6 mice and enhances effector functions of T cells to promote immune responses by disrupting the PD-1 signaling ***,we identify SHP-2 as the direct molecular target of PA for inhibiting the PD-1 signaling ***,mechanistic studies suggest that PA binds to a new druggable site in the phosphorylated PD-1 ITSM recognition site of SHP-2,inhibiting the recruitment of SHP-2 by *** together,our findings demonstrate that PA has a potential application in cancer immunotherapy and occupying the phosphorylated ITSM recognition site of SHP-2 may serve as an alternative strategy to develop PD-1 signaling *** addition,our success in target recognition provides a paradigm of target identification and confirmation for natural products.

关键词： pygenic acid A programmed death-1 immunoreceptor tyrosine-based switch motif SH2 domain-containing protein-tyrosine phosphatase-2 target identification site recognition

着色性干皮病继发眼部肿瘤2例：鳞状上皮病变和非典型纤维黄色瘤

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中华眼视光学与视觉科学杂志 2025年第1期27卷 28-35页

作者：刘璐杨宇婧龚岚毕颖文复旦大学附属眼耳鼻喉科医院病理科上海复旦大学附属眼耳鼻喉科医院眼科上海

目的: 探讨着色性干皮病(XP)继发眼表肿瘤的临床病理及免疫组织化学特征。方法: 回顾性分析。收集2000年至今复旦大学附属眼耳鼻喉科医院收治的2例着XP继发眼表肿瘤患者的临床资料, 分析组织学形态、免疫组织化学标记及预后, 并复习相... 详细信息

目的: 探讨着色性干皮病(XP)继发眼表肿瘤的临床病理及免疫组织化学特征。方法: 回顾性分析。收集2000年至今复旦大学附属眼耳鼻喉科医院收治的2例着XP继发眼表肿瘤患者的临床资料, 分析组织学形态、免疫组织化学标记及预后, 并复习相关文献。结果: 2例患者(1男1女)均自幼诊断为XP, 均因眼表新生物于复旦大学附属眼耳鼻喉科医院就诊。男性患者初次就诊年龄10岁, 并在随后17年间入院10次, 行手术切除治疗9次, 病理诊断包括左眼角结膜原位癌伴早期间质浸润(4次)、左眼角结膜鳞状上皮内瘤变(2次)、右眼睑鳞状细胞癌(1次)、左眼睑角化棘皮瘤(1次)和左眼角膜非典型纤维黄色瘤(1次)。女性患者19岁时行左眼结膜肿物手术切除, 病理诊断为原位癌伴早期间质浸润。结论: 着色性干皮病患者易在眼睑及角结膜日光暴露区域发生肿瘤, 除最常见的鳞状上皮内瘤变及鳞状细胞癌, 还可发生罕见的非典型纤维黄色瘤。XP患者继发的眼部肿瘤极易复发, 早期手术干预可控制肿瘤进展并改善预后。

关键词：着色性干皮病非典型纤维黄色瘤眼表肿瘤继发性鳞状细胞癌

On Algebraic Immunity of Trace Inverse Functions on Finite Fields of Characteristic Two

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Journal of Systems Science & Complexity 2016年第1期29卷 272-288页

作者： FENG Xiutao gong guang Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of Sciences State Key Laboratory of Information Security(Institute of Information Engineering Chinese Academy of Sciences) Department of Electrical and Computer Engineering University of Waterloo

The trace inverse functions Tr(λx^(-1)) over the finite field F_(2~n) are a class of very important Boolean functions and are used in many stream ciphers such as SFINKS,RAKAPOSHI,the simple counter stream cipher(SCSC) presented by Si W and Ding C(2012),*** order to evaluate the security of those ciphers in resistance to(fast) algebraic attacks,the authors need to characterize algebraic properties of Tr(λx^(-1)).However,currently only some bounds on algebraic immunity of Tr(λx^(-1)) are given in the public literature,for example,the NGG upper bound and the Bayev lower bound,*** paper gives the exact value of the algebraic immunity of Tr(λx^(-1)) over F_(2~n),that is,AI(Tr(λx^(-1))) =[2n^(1/2)]- 2,where n ≥ 2,A ∈ F_(2~n) and λ≠ 0,which shows that Dalai's conjecture on the algebraic immunity of Tr(λx^(-1)) is *** is more,the authors demonstrate some weak properties of Tr(λx^(-1)) against fast algebraic attacks.

关键词： Algebraic immunity boolean functions fast algebraic attacks trace inverse functions

基于离心试验的引调水工程含深层原生裂隙膨胀土层渠坡稳定性分析

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水电能源科学 2025年第2期43卷 98-103页

作者：韦松涛龚壁卫李波胡波程展林安徽理工大学土木建筑学院安徽淮南232001 长江科学院水利部岩土力学与工程重点实验室湖北武汉430010

引调水工程因跨度范围大,渠道经常穿过含深层原生裂隙区域,现场滑坡膨胀土层中实际存在的深层原生裂隙顺坡向呈8°~12°,倾向河渠。为掌握深层原生裂隙对边坡稳定性的影响,通过预设双层土工膜的方式模拟倾角为12°、48°的典型组合裂隙... 详细信息

引调水工程因跨度范围大,渠道经常穿过含深层原生裂隙区域,现场滑坡膨胀土层中实际存在的深层原生裂隙顺坡向呈8°~12°,倾向河渠。为掌握深层原生裂隙对边坡稳定性的影响,通过预设双层土工膜的方式模拟倾角为12°、48°的典型组合裂隙,开展了含深层原生裂隙边坡的离心模型试验,进一步推导了计算离心模型在离心机加速度场中边坡安全系数的简化理论。结果表明,离心加速度逐级增大过程中,边坡顶部沉降和坡面水平位移逐渐增大,同时在坡肩和坡面依次出现裂隙且随之扩展,边坡失稳并沿12°裂隙面滑动;计算得到离心模型边坡安全系数随加速度增大而逐渐降低但降低速率逐渐减小,产生破坏时的安全系数已小于1.0;进一步分析表明,土工膜裂隙面贯通率越高,边坡安全系数越低,同时裂隙面分布位置也对边坡稳定性有影响。研究结果为含深层原生裂隙边坡的分析提供了依据。

关键词：边坡裂隙离心模型试验安全系数裂隙扩展

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A NEW UNSTEADY THREE DIMENSIONAL MODEL FOR MACROMOLECULAR TRANSPORT AND WATER FILTRATION ACROSS THE ARTERIAL WALL

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Applied Mathematics and Mechanics(English Edition) 2001年第10期22卷 1155-1172页

作者： HUANG Hao(黄浩) WEN gong-bi(温功碧) Department of Mechanics and Engineering Science State Key Laboratory for Turbulence and Complicated System Research Peking University Beijing 100871 P R China Department of Mechanics and Engineering Science State Key Laboratory for Turbulence and Complicated System Research Peking University Beijing 100871 P R China

A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mitosis of endothelial cell of the arterial wall, the macromolecular transport happens surrounding the leaky cells. The arterial wall was divided into four layers: the endothelial layer, the subendothelial intima, the internal elastic lamina and the media for the convenience of research. The time-dependent concentration growth,the effect of the shape of endothelial cell and the effect of physiological parameters were analyzed. The analytical solution of velocity field and pressure field of water flow across the arterial wall were obtained; and concentration distribution of three macromolecules ; LDL,HRP and Albumin, were calculated with numerical simulation method. The new theory predicts, the maximum and distribution areas of time dependent concentration with round shape endothelial cell are both larger than that with ellipse-shape endothelial cell. The model also predicts the concentration growth is much alike that of a two-dimensional model and it shows that the concentration reaches its peak at the leaky junction where atherosclerotic formation frequently occurs and falls down rapidly in a limited area beginning from its earlier time growth to the state when macromolecular transfer approaches steadily. These predictions of the new model are in agreement with the experimental observation for the growth and concentration distribution of LDL and Albumin.

关键词： unsteady three-dimensional model flow across the arterial wall macromolecular transportation atherosclerosis concentration distribution

Research in effects of environmentally-friendly carbon black masterbatch powder rubber

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Research in effects of environmentally-friendly carbon black...