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Synthesis of cis-(±)-2-Hydroxymethyl-5-(Cytosine-1'-yl)-1,3-Oxathiolane (BCH-189)

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Chinese Chemical Letters 2001年第6期12卷 487-488页

作者： Ji Zhen LI xue peng QIU Lian Xun GAO Meng Xian DING Polymer Chemistry Laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022

The target compound BCH-189 was synthesized with high yield via four steps from benzoyloxy acetylaldehyde and p-dithiane-2,5-diol as starting materials. The synthetic route is preferable to what literature reported.

关键词： Anti-HIV total synthesis BCH-189

Strengthening strategy for high-performance friction stir lap welded joints based on 5083 Al alloy

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International Journal of Minerals,Metallurgy and Materials 2024年第11期31卷 2498-2507页

作者： Yujia Shen Jijie Wang Beibei Wang peng xue Fengchao Liu Dingrui Ni Bolv Xiao Zongyi Ma College of Material Science and Engineering Shenyang Aerospace UniversityShenyang 110136China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Binzhou Institute of Technology Shandong Key Laboratory of Advanced Aluminium Materials and TechnologyWeiqiao-UCAS Science and Technology ParkBinzhou 256606China Centre of Excellence for Advanced Materials Dongguan 523808China

During aircraft,ship,and automobile manufacturing,lap structures are frequently produced among Al alloy skins,wall panels,and *** occurrence of welding defects severely decreases mechanical properties during friction stir lap welding(FSLW).This study focuses on investigating the effects of rotation rate,multipass welding,and cooling methods on lap defect formation,microstructural evolution,and mechanical *** defects were eliminated by decreasing welding speed,applying two-pass FLSW with a small welding tool,and introducing additional water cooling,thus leading to a remarkable increase in effective sheet thickness and lap *** above strategy yielded defect-free joints with an ultrafine-grained microstructure and increased tensile shear force from 298 to 551 N/*** fracture behavior of FSLW joints was systematically studied,and a fracture factor of lap joints was proposed to predict their fracture *** reducing the rotation rate,using two-pass welding,and employing additional water cooling strategies,an enlarged,strengthened,and defect-free lap zone with refined ultrafine grains was achieved with a quality comparable to that of lap welds based on 7xxx Al ***,this study provides a valuable FSLW method for eliminating hook defects and improving joint performance.

关键词： friction stir lap welding defect control microstructure fracture mechanisms mechanical properties

Distribution behavior of inclusions in compact-strip-produced martensitic steel and its influence on mechanical properties

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Journal of Materials Science & Technology 2023年第11期142卷 98-111页

作者： Jing Wang peng xue Laiqi Zhang Li You Xiaodong Zhu Shuize Wang Yong Zhong Xinping Mao State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Research Institute Baoshan Iron&Steel Co.LtdShanghai 201999China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

The distribution behavior of inclusions in martensitic steel produced by compact strip production process(CSP-MS)and its influence on mechanical properties were systematically *** inclusions in the CSP-MS specimen are mainly composed of spherical Al_(2)O_(3)-CaO-CaS,MnS with high aspect ratio and small-sized TiN,whereas many coarse cuboidal TiN inclusions do exist in conventional martensitic steel(Con-MS).The high inclusion density of the CSP-MS specimen resulted in lower total elongation and impact toughness,and the MnS inclusions with high aspect ratio led to significantly stronger mechanical anisotropy than that for Con-MS *** in-situ tensile results indicated that when the fracture direction is parallel to MnS direction,the microcracks induced by MnS inclusions tend to propagate into the matrix,leading to the formation of valley-like features,which significantly deteriorate the properties such as the total elongation and impact *** microcracks caused by TiN inclusions are sharper than those caused by spherical Al_(2)O_(3)-CaO-CaS inclusions,and are easy to propagate into the *** work is expected to guide the optimization of the mechanical properties of martensitic steels produced by CSP process and provide a theoretical basis for the CSP process design.

关键词： Martensitic steel Compact strip production Inclusion distribution behavior Mechanical properties In-situ tensile test

Science Letters:Effect of nitrogen doping on the reduction of nitric oxide with activated carbon in the presence of oxygen

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 113-117页

作者： Xian-kai WAN Hui-xiang SHI xue-quan ZOU peng GE Da-hui WANG Institute of Environmental Engineering Zhejiang University Hangzhou 310027 China

Nitrogen doping of activated carbon （AC） was performed by annealing both in ammonia and nitric oxide, and the activities of the modified carbons for NO reduction were studied in the presence of oxygen. Results show that nitrogen atoms were incorporated into the carbons, mostly in the form of pyridinic nitrogen or pyridonic nitrogen. The effect of nitrogen doping on the activities of the carbons can be ignored when oxygen is absent, but the doped carbons show desirable activities in the low temperature regime （≤500 ℃） when oxygen is present. The role of the surface nitrogen species is suggested to promote the formation of NO2 in the presence of oxygen, and NO2 can facilitate decomposition of the surface oxygen species in the low temperature regime

关键词： Activated carbon (AC) Nitric oxide Doping Reduction

Cutaneous metastasis from esophageal squamous cell carcinoma:A case report

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World Journal of Clinical Cases 2022年第14期10卷 4676-4683页

作者： Rui-Yan Zhang Shi-Jie Zhu peng xue Sheng-Qi He Department of Oncology Wangjing HospitalChina Academy of Chinese Medicine SciencesBeijing 100102China

BACKGROUND Esophageal cancer is a common cause of cancer-related death *** metastasis of esophageal squamous cell carcinoma is rare,particularly in diffuse skin *** SUMMARY In this case report,we describe an 82-year-old male who was diagnosed with esophageal squamous cell *** tumor was staged as T4N3M1(Stage IVB).The pathological findings revealed poorly differentiated squamous cell carcinoma of the *** months after diagnosis,the patient began chemotherapy,and symptoms were relieved after four cycles of *** that,the patient returned home without a systematic physical *** year after diagnosis,the patient realized that the skin of the abdominal wall was hard and rough without pain,and the color became darker than normal *** months after diagnosis,a biopsy of the patient’s abdominal lesion revealed that the skin metastasis was derived from the *** the patient received two cycles of apatinib combined with docetaxel,but the abdominal lesion *** cycles of nivolumab were administered,but the patient eventually died of multiple organ *** This report highlights cutaneous metastasis as a late and untreatable metastasis of esophageal cancer.

关键词： Esophageal carcinoma Squamous cell carcinoma Cutaneous metastasis Immunological checkpoint inhibitor Chemotherapy Case report

Photoswitchable quantum electrodynamics in a hybrid plasmonic quantum emitter

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Chip 2023年第3期2卷 67-74页

作者： Yuan Liu Hongwei Zhou peng xue Linhan Lin Hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Beijing Computational Science Research Center Beijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

The design and preparation of quantum states free from environmen-tal decohering effects is critically important for the development of on-chip quantum systems with *** promising strategy is to harness quantum state superposition to construct decoherence-free subspace(DFS),which is termed dark ***,the exci-tation of dark states relies on anti-phase-matching on two qubits and the inter-qubit distance is of wavelength scale,which limits the de-velopment of compact quantum *** the current work,a hybrid plasmonic quantum emitter was proposed,which was composed of strongly correlated quantum emitters intermediated by a plasmonic *** turning the plasmonic loss from drawback into advantage,the anti-phase-matching rule was broken by rapidly de-caying the superposed bright state and preparing a sub-100 nm dark state with decay rate reduced by 3 orders of *** inter-estingly,the dark state could be optically switched to a single-photon emitter with enhanced brightness through photon-blockade,with the quantum second order correlation function at zero delay showing a wide range of tunability down to 0.02.

关键词： Decoherence-free subspace Plasmonics Quantum emitter On-chip quantum systems

Chain Conformation and Local Rigidity of Soluble Polyimides(II):Isomerized Polyimides in THF

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Chemical Research in Chinese Universities 2012年第2期28卷 329-333页

作者： LIU Gui-hua QIU xue-peng BO Shu-qin JI Xiang-ling State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China Polymer Composite and Engineering Laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China Graduate School of the Chinese Academy of Sciences Beijing 100049P.R.China

Two soluble isomerized polyimides（PIs） synthesized from 2,2＇-bis（3,4-dicarboxyphenyl）hexafluoropropane dianhydride（6FDA） with either 2,2＇-dimethylbenzidine（2,2＇-DMB） or 3,3＇-DMB were investigated by means of size-exclusion chromatography coupled with multi-angle laser light scattering,a viscometer and a refractive index detector in tetrahydrofuran（THF） with tetrabutylammonium bromide（TBAB） at 35 ℃.The corresponding parameters related to conformations α and ν,evaluated from the scaling relationships [η]=K η M α and R g =K g M ν,respectively,were 0.66±0.01 and 0.55±0.02 for poly（6FDA/3,3＇-DMB）,and 0.67±0.01 and 0.56±0.01 for poly（6FDA/2,2＇-DMB）,indicating a random coil conformation for both the samples in this mobile *** persistence length l p and shift factor M L（relative molecular weight per unit contour length） were estimated from the relationship between intrinsic viscosity and molecular weight for the wormlike cylinder model proposed by *** l p and M L showed that the two PIs in THF are flexible chains and exhibit some local rigidity to some extent.

关键词： Isomerized polyimide Chain conformation Local rigidity Wormlike chain Persistence length

Effect of Different Aromatic Fractions on Colloidal Property of Tahe Atmospheric Residue

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China Petroleum Processing & Petrochemical Technology 2012年第3期14卷 17-23页

作者： Yu Shuanglin Zhang Jiling Cheng Tao Rong Lili xue peng Shan Honghong State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China) Petrochemical Research Institute PetroChina Corporation CPECC East-China Design Branch

Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively. The colloi- dal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by means of the mass fraction normalized conductivity and the small-angle X-ray scattering technology （SAXS）. The results indicated that the sta- bility of Tahe atmospheric residue decreased with an increasing amount of these oil fractions. It was found that the decline of the colloidal stability was attributed to the component polarity difference between oil fractions and the atmospheric resi- due. Though the aromaticity of FCC slurry oil was higher than that of HVGO, the polarity of aromatics and resins of FCC slurry oil was lower than those of HVGO. So the degree of the colloidal stability was more seriously destroyed by FCC slurry oil. The dispersion of asphaltenes in Tahe atmospheric residue was changed by adding FCC slurry oil and HVGO. The particle size of as-ohaltenes increased alon~ with the decline of the colloidal stability

关键词： residue colloidal stability polarity SAXS particle size

Influence of coarse tailings on flocculation settlement

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1065-1074页

作者： Shi Wang xue-peng Song Xiao-jun Wang Qiu-song Chen Jian-chun Qin Yu-xian Ke School of Resources and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Department of Personnel Guangxi University of Science and TechnologyLiuzhou 545006China

The composition of tailings particles in mines plays a key role in the flocculation settlement of *** study the influence of coarse particle tailings(CPTs)on the flocculation settlement of tailings slurries(TSs),static flocculent settling tests,scanning electron microscopy observations,and laser particle size analyses were conducted using the tailings obtained from a copper *** results demonstrate that(i)in the accelerated and free settling process,CPTs did not directly settle at the bottom of graduated cylinders;instead,they were netted by the flocculent structures(FSs)and settled together more *** CPTs accelerate the rapid settlement of TSs;the acceleration effect is more obvious when the CPTs content is greater than 50 wt%.(ii)The most appropriate flocculant unit consumption(FUC)is 20 g·t-1,and no substantial increase is observed in the flocculant settling velocity with an increase in the flocculant because the effective FSs did not substantially change and thus did not lead to a notable increase in the settling velocity of the solid–liquid interface(SLI).(iii)In the effective settling space of the thickening facility,free water quickly flowed from the pores of FSs,which is reflected in the period from 0 to 1 min.

关键词： tailings slurry particle size distribution flocculent structures flocculating sedimentation solid–liquid interface