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Synthesis of tetraphenylene derivatives and their recent advances

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National Science Review 2017年第6期4卷 892-916页

作者： Jian-Wei Han xiao-shui peng Henry N.C.Wong Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic ChemistryChinese Academy of Sciences Key Laboratory for Advanced Materials Institute of Fine Chemicals School of Chemistry & Molecular Engineering East China University of Science and Technology Department of Chemistry Center of Novel Functional Molecules Institute of Molecular Functional Materials and State Key Laboratory of Synthetic ChemistryThe Chinese University of Hong Kong

The synthetic strategies towards tetraphenylene derivatives are comprehensively summarized in this *** advances in the functionalized tetraphenylene skeleton for research into their structurally unique properties are ... 详细信息

关键词： tetraphenylene aromatic chiral carbocycles eight-membered rings

Stereoselective Synthesis of (+)-△~5-Dehydrosugiyl Methyl Ether

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Chinese Chemical Letters 2001年第2期12卷 111-112页

作者： An Pai LI xiao shui peng Yong Hong GAN Xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

A stereoselective synthetic route to △~5-dehydrosugiyl methyl ether was developed from (S)-(-)-α-cyclocitral, DDQ as a better oxidant for enone was used.

关键词： synthesis diterpenoids geranic (+)-△~5-dehydrosugiyl methyl ether.

Enantioselective Total Synthesis of Four Styrylpyrone Derivatives

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Chinese Chemical Letters 2002年第6期13卷 519-520页

作者： xiao shui peng An Pai LI Tong Xing WU Xin Fu PAN Department of Chemistry&National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

The first enantioselective total synthesis of 5-acetoxygoniothalamin 1 and 5-acetoxyisogoniothalamin oxide 2 was achieved through the Sharpless kinetic resolution of racemic secondary 2- furylmethanol 5 and the Mitsunobu reaction. At the same time we developed a short synthetic route for 6R-(+)-goniothalamin 3 and (6R, 7R, 8R)-(+)-goniothalamin oxide 4. And according to this route the configuration of 5-acetoxygoniothalamin 1 was confirmed as (5S, 6S).

关键词： Enantioselective 5-acetoxygoniothalamin 5-acetoxyisogoniothalamin oxide 6R-(+)- goniothalamin (6R, 7R, 8R)-(+)-goniothalamin oxide.

Chiral Synthesis of 13-Acetyl-12-hydroxy-podocarpane-8,11,13-triene-7-one

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Chinese Chemical Letters 2001年第3期12卷 205-206页

作者： An Pai LI Yong Hong GAN xiao shui peng Tong Xing WU Xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

An enantioselective synthetic route to (+)-13-acetyl-12-hydroxy-podocarpane-8,11,13-triene-7-one 1a and (-)-13-acetyl-12-hydroxy-podocarpane-8,11,13-triene-7-one 1b was developed from (S)-(-)-alpha -cyclocitral 8a and... 详细信息

关键词： Synthesis enantioselective podocarpane anisic chiral

Mechanisms of liver injuries caused by traditional Chinese medicines

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 310-312页

作者： shui-Fang Jin Qi Pan Jin-peng Zhou xiao-Ping Pan Intensive Care Unit The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006China Institute of Liver Diseases College of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhou 310053China The Second Clinical Medical College of Zhejiang Chinese Medical University Hangzhou 310056China

Drug-induced liver injury(DILI)is a common adverse drug reaction,which can even result in liver failure[1,2].The Chinese Medical Association issued the Guidelines for the Diagnosis and Treatment of DILI based on the Roussel Uclaf Causality Assessment Method(RUCAM)in 2015[3].A previous study reported that traditional Chinese medicines(TCMs),herbal and dietary supplements,and antituberculosis drugs were the main causes of DILI in China[4].Herb-induced liver injury(HILI)refers to liver injury caused by TCMs,natural drugs,and their related preparations[5].

关键词： drugs tuberculosis TCM

Meta label associated loss for fine-grained visual recognition

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Science China(Information Sciences) 2024年第6期67卷 230-247页

作者： Yanchao LI Fu xiao Hao LI Qun LI shui YU School of Computer Science Nanjing University of Posts and Telecommunications School of Network Engineering Zhoukou Normal University School of Computer Science University of Technology Sydney

Recently, intensive attempts have been made to design robust models for fine-grained visual recognition, most notably are the impressive gains for training with noisy labels by incorporating a reweighting strategy into a meta-learning framework. However, it is limited to up or downweighting the contribution of an instance for label reweighting approaches in the learning process. To solve this issue, a novel noise-tolerant method with auxiliary web data is proposed. Specifically, first, the associations made from embeddings of well-labeled data with those of web data and back at the same class are measured. Next, its association probability is employed as a weighting fusion strategy into angular margin-based loss, which makes the trained model robust to noisy datasets. To reduce the influence of the gap between the well-labeled and noisy web data, a bridge schema is proposed via the corresponding loss that encourages the learned embeddings to be coherent. Lastly, the formulation is encapsulated into the meta-learning framework, which can reduce the overfitting of models and learn the network parameters to be noise-tolerant. Extensive experiments are performed on benchmark datasets, and the results clearly show the superiority of the proposed method over existing state-of-the-art approaches.

关键词： label associated loss weighting noisy samples fine-grained visual recognition noise-tolerant learning meta-learning

Lower extremity peripherally inserted central catheter placement ectopic to the ascending lumbar vein:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1430-1436页

作者： xiao-Ju Zhu Ling Zhao Na peng Jia-Min Luo shui-Xia Liu Cancer Center Daping HospitalArmy Medical UniversityChongqing 400042China

BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients with superior vena cava syndrome(SVCS).We report the case of a patient with a lower extremity PICC ectopic to the ascending lumbar vein,to indicate and verify PICC catheterisation in the lower extremity is safe and *** hope to provide different per-spectives for clinical PICC venipuncture to get the attention of *** SUMMARY On 24 August 2022,a 58-year-old male was admitted to our department due to an intermittent cough persisting for over a month,which worsened 10 d *** and laboratory investigations suggested the patient with pulmonary malignancy and *** was not an absolute contraindication in this *** extremity venipuncture is the preferred technique because administering upper extremity venous transfusion to patients with SVCS can exacerbate oedema in the head,neck,and upper *** patient and his family were informed about the procedure,and informed consent was *** successful puncture and prompt treatment,the patient was discharged,experiencing some relief from *** Inferior vena cava catheterisation is rare and important for cancer patients with SVCS,particularly in complex situations involving ectopic placement.

关键词： Superior vena cava syndrome Peripherally inserted central catheter Ascending lumbar vein Complications Case report

Dynamic simulation of GEH-IES with distributed parameter characteristics for hydrogen-blending transportation

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Frontiers in Energy 2024年第4期18卷 506-524页

作者： Dengji ZHOU Jiarui HAO Wang xiao Chen WANG Chongyuan shui Xingyun JIA Siyun YAN Key Laboratory of Power Machinery and Engineering of the Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China Sichuan Research Institute Shanghai Jiao Tong UniversityChengdu 610042China West Pipeline Company National Petroleum and Natural Gas Pipe Network Group Co.Ltd.Urumqi 830012China Institute of Intelligent Manufacturing Modern Industry Xinjiang UniversityUrumqi 830046China

For the purpose of environment protecting and energy saving,renewable energy has been distributed into the power grid in a considerable ***,the consuming capacity of the power grid for renewable energy is relatively *** an effective way to absorb the excessive renewable energy,the power to gas(P2G)technology is able to convert excessive renewable energy into ***-blending natural gas pipeline is an efficient approach for hydrogen ***,hydrogen-blending natural gas complicates the whole integrated energy system(IES),making it more problematic to cope with the equipment failure,demand response and dynamic ***,dynamic simulation of distribution parameters of gas-electricity-hydrogen(GEH)energy system,especially for hydrogen concentration,still remains a *** dynamics of hydrogen-blending IES is *** tackle the issue,an iterative solving framework of the GEH-IES and a cell segment-based method for hydrogen mixing ratio distribution are proposed in this *** typical numerical cases studying the conditions under which renewables fluctuate and generators fail are conducted on a real-word *** results show that hydrogen blending timely and spatially influences the flow parameters,of which the hydrogen mixing ratio and gas pressure loss along the gas pipeline are negatively correlated and the response to hydrogen mixing ratio is ***,the hydrogen-blending amount and position also have a significant impact on the performance of the compressor.

关键词： gas-electricity IES dynamic simulation hydrogen blending power to gas(P2G) renewable energy

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui peng Chen peng‑Fei Wang xiao‑Wu Li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity