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Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： Xiang Zhou zhi-Yong zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

Electrical characteristics of a fractional-order 3×n Fan network

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Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： zhi-zhong Tan Xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： ling-ling Chen Ren-Fei Cao Hua Ke zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization

Research on the MPPT of Photovoltaic Power Generation Based on Improved WOA and P&O under Partial Shading Conditions

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Energy Engineering 2024年第4期121卷 951-971页

作者： Jian zhong Lei Zhang ling Qin School of Electrical Engineering Nantong UniversityNantong226019China

Partial shading conditions(PSCs)caused by uneven illumination become one of the most common problems in photovoltaic(PV)systems,which can make the PV power-voltage(P-V)characteristics curve show *** maximum power point tracking(MPPT)methods have shortcomings in tracking to the global maximum power point(GMPP),resulting in a dramatic decrease in output *** order to solve the above problems,intelligent algorithms are used in ***,the existing intelligent algorithms have some disadvantages,such as slow convergence speed and large search ***,an improved whale algorithm(IWOA)combined with the P&O(IWOA-P&O)is proposed for the MPPT of PV power generation in this ***,IWOA is used to track the range interval of the GMPP,and then P&O is used to accurately find the MPP in that *** with other algorithms,simulation results show that this method has an average tracking efficiency of 99.79%and an average tracking time of 0.16 s when tracking ***,experimental verification is conducted,and the results show that the proposed algorithm has better MPPT performance compared to popular particle swarm optimization(PSO)and PSO-P&O algorithms.

关键词： Photovoltaic power generation maximum power point tracking whale algorithm perturbation and observation

Clinical analysis of multiple primary gastrointestinal malignant tumors:A 10-year case review of a single-center

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1204-1212页

作者： Cheng-Lou Zhu ling-zhi Peng The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Surgical Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Multiple primary malignant tumors(MPMTs)was first described by Billroth as early as 1889,with the first report published by Warren and Gates in *** then,numerous cases have been reported.A literature review of 1104269 patients with cancer revealed that the incidence of MPMTs ranged from 0.73 to 11.7%.In recent years,however,there has been a significant upward trend in the incidence of this phenomenon,which may be associated with many different factors,including the advancement of modern diagnostic procedures facilitating the examination and diagnosis of more MPMTs,increased exposure to chemotherapy and radiotherapy that exacerbate the risk of new malignant tumors in patients with cancer,and prolonged survival of patients with cancer allowing sufficient time for the development of new primary *** To analyze the incidence,clinical features,treatment factors,prevalence,and prognosis of patients with MPMTs in the gastrointestinal tract treated in a single ***,we analyzed the different tumor combinations,time interval between the occurrence of tumors,and *** This retrospective cohort study analyzed 8059 patients with pathologically confirmed gastrointestinal malignant tumors treated at the Gansu Province Hospital in Lanzhou,Gansu,China between June 2011 and June *** these,85 patients had *** clinical features,treatment factors,prevalence,and prognosis of this latter cohort were *** The incidence of MPMTs in patients with gastrointestinal malignant tumors was 1.05%(85/8059),including 83 double primary malignant tumors and two triple primary malignant tumors of which 57(67.06%)were synchronous MPMTs(SMPMTs)and 28(32.94%)were metachronous MPMTs(MMPMTs).The most frequent associations were found between the rectum colon cancers within the SMPMT category and the gastric-colon cancers within the MMPMT *** the MMPMTs,the median interval was 53 *** overall 1-,3-and 5-year survival rates f

关键词： Multiple primary malignant tumors Clinical characteristics Gastrointestinal tract Prognosis Epidemiology

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1811-1823页

作者： zhong-lin Wang zhi-hua Gong Quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Subdural effusion associated with COVID-19 encephalopathy: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1799-1803页

作者： zhi-Yuan Xue zhong-Lin Xiao Ming Cheng Tao Xiang Xiao-Li Wu Qiao-ling Ai Yang-ling Wu Tao Yang Department of Rehabilitation Medicine Chengdu Jinniu District People’s HospitalChengdu 610000Sichuan ProvinceChina Department of Rehabilitation Medicine The General Hospital of the Western Theater Command of the People’s Liberation Army of ChinaChengdu 610000Sichuan ProvinceChina

BACKGROUND The precise mechanism by which severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)impacts the central nervous system remains unclear,with manifestations spanning from mild symptoms(e.g.,olfactory and gustatory deficits,hallucinations,and headache)to severe complications(e.g.,stroke,seizures,encephalitis,and neurally demyelinating lesions).The occurrence of single-pass subdural effusion,as described below,is extremely *** SUMMARY A 56-year-old male patient presented with left-sided limb weakness and slurred speech as predominant clinical *** comprehensive imaging and diagnostic assessments,he was diagnosed with cerebral infarction complicated by hemorrhagic transformation affecting the right frontal,temporal,and parietal *** addition,an intracranial infection with SARS-CoV-2 was identified during the rehabilitation process;consequently,an idiopathic subdural effusion ***,the subdural effusion underwent absorption within 6 d,with no recurrence observed during the 3-month *** Subdural effusion is a potentially rare intracranial complication associated with SARS-CoV-2 infection.

关键词： Cerebral infarction Hemorrhagic transformation Subdural effusion COVID-19 encephalopathy Novel coronavirus infection Brain fog Case report

Nickel Sulfide Modified NiCu Nanoalloy with Excellent Oxygen Evolution Reaction Properties Prepared through Electrospinning and Heat Treatment

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 320-326页

作者：李涛凌帅 zhong Shujie LOU Qiongyue Department of Materials Engineering School of Mechanical EngineeringChengdu UniversityChengdu 610106China

Ni^(2+)/Cu^(2+)/SO_(4)^(2-)/polyvinyl alcohol precursor fibers with uniform diameters were prepared through ***-based composite nanoalloys containing Ni,Cu,and S were prepared through heat treatment in an Ar *** experimental results show that the main components of the prepared nanoalloys are NiCu,Ni_(3)S_(2),Ni,and *** nanoalloys exhibit fine grain sizes about 200-500 nm,which can increase with increasing heat treatment *** test results show that the nickel sulfidemodified NiCu nanoalloy composites exhibit excellent oxygen evolution reaction properties,and the oxygen evolution reaction properties gradually improve with the increasing heat treatment *** sample prepared at 1 000℃ for 40 min show a low overpotential of 423 mV and a small Tafel slope of 134 mV·dec^(-1) at a current density of 10 mA·cm^(-2).

关键词： NiCu nanoalloy Ni_(3)S_(2) structure transformation oxygen evolution reaction

Pig H3K4me3,H3K27ac,and gene expression profiles reveal reproductive tissue-specific activity of transposable elements

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Zoological Research 2024年第1期45卷 138-151页

作者： Tao Jiang zhi-Min Zhou Zi-Qi ling Qing Zhang zhong-Zi Wu Jia-Wen Yang Si-Yu Yang Bin Yang Lu-Sheng Huang National Key Laboratory of Pig Genetic Improvement and Germplasm Innovation Jiangxi Agricultural UniversityNanchangJiangxi 330045China

Regulatory sequences and transposable elements(TEs)account for a large proportion of the genomic sequences of species;however,their roles in gene transcription,especially tissue-specific expression,remain largely *** serve as an excellent animal model for studying genomic sequence biology due to the extensive diversity among their wild and domesticated ***,we conducted an integrated analysis using H3K27ac ChIP-seq,H3K4me3 ChIP-seq,and RNA-seq data from 10 different tissues of seven fetuses and eight closely related adult *** aimed to annotate the regulatory elements and TEs to elucidate their associations with histone modifications and mRNA expression across different tissues and developmental *** on correlation analysis between mRNA expression and H3K27ac and H3K4me3 peak activity,results indicated that H3K27ac exhibited stronger associations with gene expression than ***,1.45%of TEs overlapped with either the H3K27ac or H3K4me3 peaks,with the majority displaying tissue-specific ***,a TE subfamily(LTR4C_SS),containing binding motifs for SIX1 and SIX4,showed specific enrichment in the H3K27ac peaks of the adult and fetal ***-seq analysis also revealed widespread expression of TEs in the exons or promoters of genes,including 4688 TE-containing transcripts with distinct development stage-specific and tissue-specific *** note,1967 TE-containing transcripts were enriched in the *** identified a long terminal repeat(LTR),MLT1F1,acting as a testis-specific alternative promoter in SRPK2(a cell cycle-related protein kinase)in our pig *** element was also conserved in humans and mice,suggesting either an ancient integration of TEs in genes specifically expressed in the testes or parallel evolutionary ***,our findings demonstrate that TEs are deeply embedded in the genome and exhibit important tissue-specific biological functions,particularly in the reproductive

关键词： Transposable elements Porcine Histone modification Alternative promoter TE-containing transcript