检索结果-南通市图书馆

Time-frequency analysis of internal waves generated by a towed and self-propelled submerged body model

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2023年第6期35卷 1191-1207页

作者： yu-hang li Fei-yu Chen li-ping Qin Ke Chen yun-xiang You Zhengzhou Electromechanical Engineering Research Institute Zhengzhou450015China Henan Key Laboratory of Underwater Intelligence Equipment Zhengzhou450015China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversityShanghai200240China

The spectrogram,based on a short-time Fourier transform,can visualize the time-dependent frequency spectrum of waves and is easy to compute.This time-frequency analysis method provides crucial information about waves generated by moving vessels and has been utilized to analyze Kelvin ship waves and internal waves.To further study the internal waves induced by a submerged body,an experiment is conducted for the towed and self-propelled SUBOFF model in a stratified fluid.The internal wave elevation signals are captured using electronic conductivity probes.Comparing with the calculation results of theoretical model,the high-frequency component of internal waves is identified.The high-frequency component has the exact same characteristics in both the towed and self-propelled model experiment and is consistent with the theoretical results for all Froude numbers.Therefore,this component is composed mainly of lee waves.Through spectral characteristics identification,a low-frequency component is discovered in the spectrogram in addition to the lee wave component.The intensity of the low-frequency component is tightly related to the vortex structure behind the submerged body.The vortex structure depends on the net momentum imparted by the submerged body.Therefore,this component is composed mainly of wake waves induced by the vortex structure.

关键词： Stratified fluid internal waves submerged body experimental study time-frequency analysis

Microstructural development and wear properties analyses of Fe-based coatings on bainitic steel by laser cladding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2022年第4期29卷 687-697页

作者： Run-feng Peng Min Zhang yu-hang li yue-long yu Ying-chun Guan Zhun-li Tan School of Mechanical Electronic and Control EngineeringMaterials Science&Engineering Research CenterBeijing Jiaotong UniversityBeijing 100044China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Beihang UniversityBeijing 100083China Hefei Innovation Research Institute of Beihang University Hefei 230013AnhuiChina

Wear-resistant Fe-based coating was prepared by high-speed laser cladding on bainitic steel.The influence of laser scanning speed on microstructure,microhardness,and wear resistance of cladding coating was investigated.Scanning electron microscopy results showed that the coating was mainly composed of dendrite and interdendrite.Scanning electron microscope images were converted by binary algorithm to facilitate statistics of dendrite and interdendrite area.Statistical results indicate that by accelerating the scanning speed,the interdendrite eutectic structure increased.According to energydispersive X-ray spectroscopy and X-ray diffraction results,the interdendrite was enriched with elements Cr,Mo,and B,and main structures in the coating wereα-Fe,γ-Fe,and M(23)C_(6).The hardness of the coating was much higher than that of the substrate.Elements diffused from coating to substrate,resulting in a transition zone of hardness.Moreover,with an increase in the scanning speed,the diffusion of elements at the coating–matrix interface decreased,while the hardness and wear resistance of the coating increased.Grain refinement and interdendrite(γ-Fe,M_(23)C_(6))increasing due to high scanning speed were the major contributors to the increase in hardness and wear resistance.

关键词： Laser cladding Microstructure Wear property Fe-based coating Bainitic steel

Photocatalytic Cr(Ⅵ)reduction over MIL-88A(Fe)on polyurethane sponge: From batch to continuous-flow operation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第7期34卷 236-239页

作者： Xiao-Hong Yi Ya Gao Chong-Chen Wang yu-hang li Hong-yu Chu Peng Wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering.Beijing University of Civil Engineering and ArchitectureBeijing 100044China Beijing Energy Conservation&Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center Beijing University of Civil Engineering and ArchitectureBeijing100044China

MIL-88A(Fe)@sponge(MS) was synthesized by a dip-coating method, which displayed efficient photocatalytic Cr(Ⅵ) reduction efficiency under both low power LED UV light and real solar light irradiation. It was observed that MS(0.2 g/L) could remove 100% Cr(Ⅵ)(10 mg/L) by adding 0.4 mmol/L tartaric acid(TA) without adjusting pH(pH 5.05) within 6.0 min and 3.0 min under UV light and real solar light irradiation, respectively. Besides, the photo-induced e-and radicals(O_(2)^(·-) and CO_(2)^(·-)) were found to play the momentous roles in the MS/TA/UVL/Cr(Ⅵ) system by the scavenger experiments and electron spin resonance(ESR) tests. MS was also filled into a fixed-bed reactor to test the possibility of long-term Cr(Ⅵ)reduction operation in TA/UVL system. As expected, the results revealed that MS could still maintain 100% activity up to 60 h. These results demonstrated that MIL-88A(Fe) might be the potentially efficient catalyst for large-scale wastewater treatment in the near future.

关键词： MIL-88A(Fe) Polyurethane sponge Cr(Ⅵ)reduction Tartaric acid Continuous operation

Investigating Why Sulfurization Can Greatly Improve Ethanol Selectivity for Carbon Dioxide Electroreduction

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2022年第10期4卷 3319-3328页

作者： Qian-yu Wang yu-hang li yu Zhao yu-yu Chen Bi-Jun Geng Rong-Kai Ye Qiong liu Xiao-Qing liu Ye-Xiang Tong yue-Jiao Zhang Jun Cheng Ping-Ping Fang Jian-Qiang Hu Jian-Feng li Zhong-Qun Tian MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry The Key Laboratory of Low-Carbon Chem&Energy Conservation of Guangdong ProvinceSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510275 Department Key Laboratory of Fuel Cell Technology of Guangdong Province Nanobiological Medicine CenterSchool of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640 State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMCollege of Chemistry and Chemical EngineeringCollege of EnergyXiamen UniversityXiamen 361005

Carbon dioxide(CO_(2))electroreduction of products using renewable electricity sources is a promising avenue for chemical energy storage that is attracting increasing attention.Considerable effort has been focused on improving the activity and selectivity for CO_(2)electroreduction of C2+products,especially for ethanol.However,studies of this process’s underlying mechanism are still lacking.

关键词： surface-enhanced Raman spectroscopy CO_(2)electroreduction electrocatalysis operando spectroscopy mechanisms

Current noises in a topological Josephson junction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 75-81页

作者： yu-hang li Jie liu JunTao Song Hua Jiang Qing-Feng Sun XinCheng Xie International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Department of Applied Physics School of Science Xi'an Jiaotong University Xi'an 710049 China Department of Physics and Hebei Advanced Thin Film Laboratory Hebei Normal University Shijiazhuang 050024 China College of Physics Optoelectronics and Energy Soochow University Suzhou 215006 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing 100190 China

We study the transport properties of a superconductor-quantum spin Hall insulator-superconductor Josephson junction both in the absence and in the presence of a DC bias voltage. As the system is predicted to host Majorana fermions at its interfaces,the Andreev bond states are supposed to exhibit a distinct 4π periodicity in the superconducting phase difference, namely the fractional Josephson effect. Using the non-equilibrium Green's function method, we calculate the current and the related current noise based on a tight-binding Hamiltonian. Our direct results show that the fractional Josephson effect can not be seen in equilibrium junctions. While in non-equilibrium junctions, this effect can be confirmed by the multiple Andreev reflections induced peaks of the non-equilibrium noise, which appear at discrete frequencies ω = ne V with n being an integer number.

关键词： Josephson 连接噪音 Hamiltonian 拓扑非平衡超导体计算电流

Traditional Chinese Medicine Synonymous Term Conversion:A Bidirectional Encoder Representations from Transformers-Based Model for Converting Synonymous Terms in Traditional Chinese Medicine

在线全文

学校读者我要写书评

暂无评论

World Journal of Traditional Chinese Medicine 2023年第2期9卷 224-233页

作者： Lu Zhou Chao-Yong Wu Xi-Ting Wang Shuang-Qiao liu Yi-Zhuo Zhang yue-Meng Sun Jian Cui Cai-Yan li Hui-Min yuan Yan Sun Feng-Jie Zheng Feng-Qin Xu yu-hang li School of Traditional Chinese Medicine Beijing University of Chinese MedicineChina Traditional Chinese Medicine(Zhong Jing)School Henan University of Chinese MedicineChina Shenzhen Hospital of Beijing University of Chinese Medicine China School of life Sciences Beijing University of Chinese Medicine China Department of Medicine Columbia University Irving Medical CenterNew YorkUSA TCM Information Science Research Center School of Traditional Chinese MedicineBeijing University of Chinese MedicineChina Xiyuan Hospital of China Academy of Chinese Medical Sciences BeijingChina

Background:The medical records of traditional Chinese medicine(TCM)contain numerous synonymous terms with different descriptions,which is not conducive to computer-aided data mining of TCM.However,there is a lack of models available to normalize synonymous TCM terms.Therefore,construction of a synonymous term conversion(STC)model for normalizing synonymous TCM terms is necessary.Methods:Based on the neural networks of bidirectional encoder representations from transformers(BERT),four types of TCM STC models were designed:Models based on BERT and text classification,text sequence generation,named entity recognition,and text matching.The superior STC model was selected on the basis of its performance in converting synonymous terms.Moreover,three misjudgment inspection methods for the conversion results of the STC model based on inconsistency were proposed to find incorrect term conversion:Neuron random deactivation,output comparison of multiple isomorphic models,and output comparison of multiple heterogeneous models(OCMH).Results:The classification-based STC model outperformed the other STC task models.It achieved F1 scores of 0.91,0.91,and 0.83 for performing symptoms,patterns,and treatments STC tasks,respectively.The OCMH method showed the best performance in misjudgment inspection,with wrong detection rates of 0.80,0.84,and 0.90 in the term conversion results for symptoms,patterns,and treatments,respectively.Conclusion:The TCM STC model based on classification achieved superior performance in converting synonymous terms for symptoms,patterns,and treatments.The misjudgment inspection method based on OCMH showed superior performance in identifying incorrect outputs.

关键词： Bidirectional encoder representations from transformers misjudgment inspection synonymous term conversion traditional Chinesem edicine

Regulatory effect of a Chinese herbal medicine formula on nonalcoholic fatty liver disease

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2019年第34期25卷 5105-5119页

作者： Jia-Min Yang Yan Sun Min Wang Xin-Lei Zhang Shu-Jing Zhang yu-Shan Gao lin Chen Meng-Yao Wu Lu Zhou yu-Mei Zhou yue Wang Feng-Jie Zheng yu-hang li School of Traditional Chinese Medicine Beijing University of Chinese Medicine

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)has become a major cause of chronic liver disease.The Chinese herbal medicine(CHM)Dachaihu decoction(DCHD)has been proved to treat NAFLD with good efficacy in previous studies.Based on the TCM principle of formula formation,we divided DCHD into soothing liver part,invigorating spleen part,and dredging intestine part.Marshall officially proposed the concept of“intestinal-hepatic axis”,which systematically explains the interactions between the intestine and liver.We hypothesized that the effect of CHM on NAFLD is achieved by regulating the liver and intestine.Thus,we aimed to investigate the possible effect of a CHM formula on NAFLD in a rat model.AIM To investigate the effects of a CHM formula(a decoction of Chinese thorowax root,scutellaria root,and white peony root)on NAFLD and its regulatory effect on the“intestinal-liver”axis.METHODS Sixty rats were randomly divided into control,model,pioglitazone hydrochloride(PH),and CHM(a decoction of Chinese thorowax root,scutellaria root,and white peony root)groups.An NAFLD rat model was established using a high-fat highfructose diet for 16 wk.From the 13th week,rats were administered with PH or a decoction of Chinese thorowax,scutellaria,and white peony root(CHM group)for 4 wk.Rats in the control group and model group were administered with an equal volume of distilled water.At the end of the study,blood was collected via the abdominal aorta.liver tissues were harvested and any morphological changes were observed by hematoxylin-eosin(HE)staining,Oil red O staining,and Masson staining.In addition,blood lipids,liver function markers,and triglyceride(TG)in liver tissues were analyzed.The levels of transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),Toll-like receptor-4(TLR4),and nuclear factor-kappa B(NF-кB)in liver tissues and secreted immunoglobulin A(sIgA)in intestinal tissues were analyzed by EliSA,and protein and mRNA expression of occludin and zonula occludens-1(ZO-1)in the intestine were measured usi

关键词： Non-alcoholic fatty liver disease Chinese herbal medicine liver function Intestinal-hepatic axis

Efficient production optimization for naturally fractured reservoir using EDFM

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2023年第4期20卷 2268-2281页

作者： Jian-Chun Xu Wen-Xin Zhou hang-yu li Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Naturally fractured reservoirs make important contributions to global oil and gas reserves and production.The modeling and simulation of naturally fractured reservoirs are different from conventional reservoirs as the existence of natural fractures.To address the development optimization problem of naturally fractured reservoirs,we propose an optimization workflow by coupling the optimization methods with the embedded discrete fracture model(EDFM).Firstly,the effective and superior performance of the workflow is verified based on the conceptual model.The stochastic simplex approximate gradient(StoSAG)algorithm,the ensemble optimization(EnOpt)algorithm,and the particle swarm optimization(PSO)algorithm are implemented for the production optimization of naturally fractured reservoirs based on the improved versions of the Egg model and the PUNQ-S3 model.The results of the two cases demonstrate the effectiveness of this optimization workflow by finding the optimal well controls which yield the maximum net present value(NPV).Compared to the initial well control guess,the final NPV obtained from the production optimization of fractured reservoirs based on all three optimization algorithms is significantly enhanced.Compared with the optimization results of the PSO algorithm,StoSAG and EnOpt have significant advantages in terms of final NPV and computational efficiency.The results also show that fractures have a significant impact on reservoir production.The economic efficiency of fractured reservoir development can be significantly improved by the optimization workflow.

关键词： Production optimization Naturally fractured reservoir Embedded discrete fracture method StoSAG algorithm PSO algorithm

A multicenter retrospective study on the real-world outcomes of autologous vs. allogeneic hematopoietic stem cell transplantation for peripheral T-cell lymphoma in China

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2021年第13期134卷 1584-1592页

作者： Zhen-Yang Gu yu-Jun Dong Xiao-Rui Fu Nai-Nong li Yao liu Xiao-Xiong Wu Yi-Ni Wang yu-hang li Han-yun Ren Ming-Zhi Zhang Xiao-Fan li Mai-Hong Wang Ya-Mei Wu Dai-Hong liu Zhao Wang liang-Ding Hu Wen-Rong Huang Department of Hematology The Fifth Medical Center of Chinese PLA General HospitalBeijing 100071China Department of Hematology Peking University First HospitalBeijing 100034China Department of Oncology Zhengzhou University First Affiliated HospitalZhengzhouHenan 450000China Department of Hematology Fujian Institute of HematologyFuzhouFujian 350000China Center of Hematology Xinqiao HospitalArmy Medical UniversityChongqing 400037China Department of Hematology Capital Medical University Affiliated Beijing Friendship HospitalBeijing 100050China

Background:There were few studies on real-world data about autologous hematopoietic stem cell transplantation(auto-HSCT)or allogeneic HSCT(allo-HSCT)in peripheral T-cell lymphoma(PTCL).This study aimed to investigate the clinical outcomes of patients who received auto-HSCT or allo-HSCT in China.Methods:From July 2007 to June 2017,a total of 128 patients who received auto-HSCT(n=72)or allo-HSCT(n=56)at eight medical centers across China were included in this study.We retrospectively collected their demographic and clinical data and compared the clinical outcomes between groups.Results:Patients receiving allo-HSCT were more likely to be diagnosed with stage III or IV disease(95%vs.82%,P=0.027),bone marrow involvement(42%vs.15%,P=0.001),chemotherapy-resistant disease(41%vs.8%,P=0.001),and progression disease(32%vs.4%,Plity rate in auto-HSCT recipients was 6%(4/63)compared with 27%(14/54)for allo-HSCT recipients(P=0.004).Subanalyses showed that patients with lower prognostic index scores for PTCL(PIT)who received auto-HSCT in an upfront setting had a better outcome than patients with higher PIT scores(3-year OS:85%vs.40%,P=0.003).Patients with complete remission(CR)undergoing auto-HSCT had better survival(3-year OS:88%vs.48%in allo-HSCT,P=0.008).For patients beyond CR,the outcome of patients who received allo-HSCT was similar to that in the atuo-HSCT group(3-year OS:51%vs.46%,P=0.300).Conclusions:Our study provided real-world data about auto-HSCT and allo-HSCT in China.Auto-HSCT seemed to be associated with better survival for patients in good condition(lower PIT score and/or better

关键词： Peripheral T-cell lymphoma Auto-HSCT Allo-HSCT PIT score Remission status