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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian Li-Cai Liu zhi-hao chen Yuan Liu Yin Li Qingjiang Li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organoborons are useful building blocks and key structural elements in functional *** previous synthesis relied on the famous Matteson reaction or the late-stage borylative modification of alkynes or ***,the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively *** report herein that B(MIDA)-propargylic alcohols(BPAs) are a useful type of borylated building *** two complementary functional group handles(alkyne and hydroxyl) in close proximity,the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates,including α,β-unsaturated acylborons,α-S/P-substituted allenylborons,boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine,some of which are otherwise challenging targets using other synthetic methods.

关键词： organoboron diverse synthesis sigmatropic rearrangement heteroarene amide

Laser-induced cleaning for modulating hydrophilic/hydrophobic properties of Ti-6Al-4V alloy surface microstructure

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Tungsten 2024年第4期6卷 669-674页

作者： zhi-hao chen Bao Liu Yan-Hu Zhang Institute of Advanced Manufacturing and Modern Equipment Technology Jiangsu University Automotive Engineering Research Institute Jiangsu University Department of Mechanical Engineering City University of Hong Kong

Surface treatment of metals is a primary method to prevent equipment *** significant efforts and notable advancements,many existing technologies incur high costs and demanding technical requirements,particularly in th... 详细信息

关键词： TITANIUM

100 cm^(2) Organic Photovoltaic Cells with 23%Efficiency under Indoor Illumination

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Chinese Journal of Polymer Science 2022年第8期40卷 979-988,I0011页

作者： Yong Cui Hui-Feng Yao Ye Xu Peng-Qing Bi Jian-Qi Zhang Tao Zhang Ling Hong zhi-hao chen zhi-Xiang Wei Xiao-Tao hao Jian-Hui Hou Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China CAS key laboratory of nanosystem and hierarchical fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan250100China

The application of organic photovoltaic(OPV)cells to drive off-grid microelectronic devices under indoor light has attracted broad *** organic semiconductors intrinsically have less ordered intermolecular packing than inorganic materials,the relatively larger energetic disorder is one of the main results that limit the photovoltaic efficiency of the OPV cells at low carrier ***,we optimize the alkyl chains of non-fullerene acceptors to get suppressed energetic *** find the optimal acceptor DTz-R1 with the shortest alkyl chain has the strongest crystalline property and lowest energetic *** a result,over 26%efficiency is recorded for the 1 cm^(2) OPV cells under a light-emitting diode illumination of 500 *** also fabricate a 100 cm^(2) cell device and get a PCE of 23.0%,which is an outstanding value for large-area OPV *** results suggest that modulation of the energetic disorder is of great importance for further improving the efficiency of OPV cells,especially for indoor applications.

关键词： Organic photovoltaic cells Low light intensity Energetic disorder Energy loss Power conversion efficiency

Hoffa's fracture in a five-year-old child diagnosed and treated with the assistance of arthroscopy:A case report

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World Journal of Clinical Cases 2022年第36期10卷 13458-13466页

作者： zhi-hao chen Hai-Fan Wang hao-Yu Wang Fei Li Xue-Feng Bai Jian-Long Ni zhi-Bin Shi The First Department of Orthopaedics The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Department of Orthopaedics Xi’an Daxing HospitalXi'an 710016Shaanxi ProvinceChina

BACKGROUND Hoffa’s fracture is a coronal-oriented fracture of the femoral *** is rarely observed in pediatric patients that isolated coronal fracture of the medial femoral condyle accompanies an intact lateral femoral *** a few cases involving Hoffa’s fracture of the medial femoral condyle have been reported in patients with undeveloped *** a fracture cannot be observed by routine imaging examinations,thus resulting in possible misdiagnosis and further treatment *** SUMMARY A 5-year-old boy with Hoffa’s fracture of the medial femoral condyle suffered from right knee pain and severe swelling after being hit by a heavy *** patient was misdiagnosed and initially treated in a local primary healthcare *** improvement in his right knee’s extension was observed following conservative treatment for 2 *** patient was transferred to our hospital,rediagnosed using arthroscopy,and underwent open reduction and internal *** therapeutic outcome was satisfactory with the screws removed 7 mo after *** the final follow-up of 40 mo,the range of motion in the knee had *** was no varus-valgus *** Hoffa’s fracture is rarely seen in children aged 5 years,let alone in the medial condyle,and can easily be misdiagnosed due to limited physical and imaging *** Hoffa’s fracture in preschool children should be confirmed based on arthroscopic *** reduction and internal fixation should be performed to protect the articular surface and prevent long-term complications.

关键词： Hoffa’s fracture Pediatrics Medial femoral condyle Missed diagnosis Arthroscopy Open reduction-internal fixation Case report

Spontaneous expulsion of a duodenal lipoma after endoscopic biopsy: A case report

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World Journal of Gastroenterology 2022年第34期28卷 5086-5092页

作者： zhi-hao chen Li-Hong Lv Wen-Sheng Pan Yi-Miao Zhu Department of Gastroenterology Zhejiang Provincial People’s HospitalHangzhou 310014Zhejiang ProvinceChina Affiliated Hospital People’s Hospital of Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Department of Gastroenterology Xianju County People’s HospitalTaizhou 317300Zhejiang ProvinceChina

BACKGROUND Gastrointestinal(GI)lipomas are benign submucosal tumors of mature adipocytes that arise mainly in the colon and stomach,sometimes in the ileum and jejunum,and rarely in the *** with symptomatic lipomas require endoscopic or surgical *** expulsion of lipomas after biopsy is a rare condition that has limited case *** SUMMARY A 56-year-old man presented to our hospital with intermittent postprandial epigastric ***(EGD)revealed a 10-mm soft yellowish submucosal lesion with the“pillow sign,”located in the second portion of *** ultrasonography(EUS)using a 12-MHz catheter probe showed a hyperechoic,homogenous,and round solid lesion(OLYMPUS EUS EUME2,UM-DP12-25R,12-MHz radial miniprobe,Olympus Corporation,Tokyo,Japan).Deep biopsy was performed using the bite-on-bite technique with *** examination was compatible with submucosal *** lesion spontaneously expelled 12 d after the ***-up EUS performed after 2 mo confirmed this *** Deep biopsy could lead to spontaneous GI lipoma *** might be the first step in lipoma diagnosis and treatment.

关键词： Lipoma Duodenal neoplasms Spontaneous expulsion Endoscopic biopsy Adipose tissue Case report

A boryl-migratory semipinacol rearrangement

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Science China Chemistry 2022年第4期65卷 746-752页

作者： Dong-Hang Tan zhi-hao chen Ling Yang Chang-Ting Li Fang-Hai Tu Qingjiang Li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal UniversityGuilin 541004China

The semipinacol rearrangement is one of the classic yet useful synthetic tools in organic ***,semipinacol rearrangements involving heteroatom-migration are *** herein is a boryl-migratory semipinacol rearrangement of α-hydroxyallylboronates and α-hydroxypropargylboronates triggered by diverse halogen-,oxygen-,sulfur-and seleniumcontaining *** protocol leads to a mild and facile access to organoborons bearing valuable *** σ(C-B)hyperconjugation is believed to be the key factor that leads to the observed exclusive chemoselectivity and enhanced *** utilities of the formed products were demonstrated.

关键词： 1,2-boryl migration hyperconjugation iterative cross-coupling organoborons semipinacol rearrangement sp3-B tetrasubstituted alkene

Synthesis of allenyl-B(MIDA)via hydrazination/fragmentation reaction of B(MIDA)-propargylic alcohol

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Chinese Chemical Letters 2023年第1期34卷 333-336页

作者： Jiasheng Qian zhi-hao chen Yuan Liu Yin Li Qingjiang Li Shi-Liang Huang Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou 510006China

Allenylboronates represent a very intriguing class of organoborons but are challenging to *** addition,these compounds are typically unstable,rendering the separation *** report herein a practical and concise route to a new class of stable,easy-separable allenyl B(MIDA)via a hydrazination/fragmentation of B(MIDA)-propargylic *** synthesis of optically active allenyl B(MIDA)was also *** reactivity of the resulting product was observed.

关键词： Allenyl boronate Mitsunobu reaction Mida boronates Hydrazination Fragmentation Chirality transfer

Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： zhi-Hua ZHOU zhi-hao TAN National Key Laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/*** research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in *** prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon *** article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

Non-monotonic behavior of jam probability and stretched exponential distribution in pedestrian counterflow

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CHINESE PHYSICS B 2024年第9期33卷 259-266页

作者： chen, Ze-hao Wu, zhi-Xi Guan, Jian-Yue Guangxi Normal Univ Guilin 541004 Peoples R China Lanzhou Univ Lanzhou Ctr Theoret Phys Key Lab Theoret Phys Gansu Prov Lanzhou 730000 Peoples R China Lanzhou Univ Key Lab Quantum Theory & Applicat Minist Educ Lanzhou 730000 Peoples R China

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow moving in a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians trying to move to the same target location. By means of computer simulations, we show that the complementary cumulative distribution of the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponential distribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by the flow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibits a non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around 0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristics of the pedestrians may attributed to the anticipation mechanism of collision avoidance.

关键词： traffic and crowd dynamics evolutionary game theory 02.50.Le 45.70.Vn FLOW CHARACTERISTICS DYNAMICS

P-symmetric Subharmonic Solutions for Nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： Duan zhi ZHANG zhi hao Zhao School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a *** the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2) are geometrically distinct for k_(1)/k_(2)≥(2n+1)m+1;and xk_(1),xk_(2) are geometrically distinct for k_(1)/k_(2)≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear