期刊文献+
共找到99篇文章
< 1 2 5 >
每页显示 20 50 100
基于文献计量学BSA在作物育种领域的应用现状与展望
1
作者 张刚 朱林 +2 位作者 聂豪杰 包玉国 程云龙 《遗传》 CAS CSCD 北大核心 2024年第5期360-372,共13页
为了解国内外集群分离分析法(bulked segregant analysis,BSA)在作物育种领域的研究现状与前沿动态,客观反映各国家、机构及研究人员在该领域的影响力,本文基于文献计量学分析方法使用文献计量分析软件CiteSpace对WOS(Web of Science)... 为了解国内外集群分离分析法(bulked segregant analysis,BSA)在作物育种领域的研究现状与前沿动态,客观反映各国家、机构及研究人员在该领域的影响力,本文基于文献计量学分析方法使用文献计量分析软件CiteSpace对WOS(Web of Science)数据库2000~2023年2111项和CNKI(China National Knowledge Infrastructure)数据库2003~2023年446项研究成果进行关键词共现分析、突显词分析、关键词聚类分析、聚类时间线分析及作者共被引分析。结果表明:BSA在作物育种领域应用的研究成果在国内外的发文趋势相同,国内外期刊发文量均逐年上升;在发文量国家排序中,中国排名第一、美国第二、印度第三。在CNKI数据库中华中农业大学的发文量最多,而在WOS数据库中中国农业科学院的发文量最多。国外BSA在作物育种领域应用的文章主要集中在植物科学、农学、园艺学和遗传学等学科,而国内主要集中在作物学、植物保护学、园艺学、生物学等学科;Michlmore RW、Kosambi DD和Li H这3位作者在该领域的影响力最高,而Michlmore RW、Lander ES、Li H这3位作者与其他作者有更密切的联系。国内研究的热点作物和性状分别是水稻(Oryza sativa)、大豆(Glycine max)、玉米(Zea mays L.)和抗病性、株高;国外研究的热点作物和性状分别是水稻、拟南芥(Arabidopsis thaliana)、小麦(Triticum aestivum L.)和抗病性。目前,BSA在国内集中应用于作物目标性状候选基因及作物突变体突变基因的定位和功能验证,而国外则集中应用于作物目标性状基因的精细定位和功能验证及遗传机制的解析。此外,BSA在作物育种领域应用的研究前沿分析表明,未来在该领域热点研究的对象为水稻、花生(Arachis hypogaea L.)、陆地棉(Gossypium hirsutum L.)、作物突变体和作物代谢产物。 展开更多
关键词 BSA 作物育种 文献计量分析法 CITESPACE
下载PDF
A Thermochromic, Viscoelastic Nacre-like Nanocomposite for the Smart Thermal Management of Planar Electronics 被引量:1
2
作者 Jiemin Wang Tairan Yang +6 位作者 Zequn Wang Xuhui Sun Meng An Dan Liu Changsheng Zhao gang zhang Weiwei Lei 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期182-196,共15页
Cutting-edge heat spreaders for soft and planar electronics require not only high thermal conductivity and a certain degree of flexibility but also remarkable self-adhesion without thermal interface materials, elastic... Cutting-edge heat spreaders for soft and planar electronics require not only high thermal conductivity and a certain degree of flexibility but also remarkable self-adhesion without thermal interface materials, elasticity, arbitrary elongation along with soft devices, and smart properties involving thermal self-healing, thermochromism and so on. Nacre-like composites with excellent in-plane heat dissipation are ideal as heat spreaders for thin and planar electronics. However, the intrinsically poor viscoelasticity, i.e., adhesion and elasticity, prevents them from simultaneous self-adhesion and arbitrary elongation along with current flexible devices as well as incurring high interfacial thermal impedance. In this paper, we propose a soft thermochromic composite(STC) membrane with a layered structure, considerable stretchability, high in-plane thermal conductivity(~30 Wm^(-1) K^(-1)), low thermal contact resistance(~12 mm^2 KW^(-1), 4–5 times lower than that of silver paste), strong yet sustainable adhesion forces(~4607 Jm^(-2), 2220 Jm^(-2) greater than that of epoxy paste) and self-healing efficiency. As a self-adhesive heat spreader, it implements efficient cooling of various soft electronics with a temperature drop of 20℃ than the polyimide case. In addition to its self-healing function, the chameleon-like behavior of STC facilitates temperature monitoring by the naked eye, hence enabling smart thermal management. 展开更多
关键词 Boron nitride nanosheets Nacre-inspired composites VISCOELASTIC THERMOCHROMIC Smart thermal management
下载PDF
Personalized pancreatic cancer therapy:from the perspective of mRNA vaccine
3
作者 Xing Huang gang zhang +2 位作者 Tian‑Yu Tang Xiang Gao Ting‑Bo Liang 《Military Medical Research》 SCIE CAS CSCD 2023年第4期461-477,共17页
Pancreatic cancer is characterized by inter-tumoral and intra-tumoral heterogeneity,especially in genetic alteration and microenvironment.Conventional therapeutic strategies for pancreatic cancer usually suffer resist... Pancreatic cancer is characterized by inter-tumoral and intra-tumoral heterogeneity,especially in genetic alteration and microenvironment.Conventional therapeutic strategies for pancreatic cancer usually suffer resistance,highlighting the necessity for personalized precise treatment.Cancer vaccines have become promising alternatives for pancreatic cancer treatment because of their multifaceted advantages including multiple targeting,minimal nonspecific effects,broad therapeutic window,low toxicity,and induction of persistent immunological memory.Multiple conventional vaccines based on the cells,microorganisms,exosomes,proteins,peptides,or DNA against pancreatic cancer have been developed;however,their overall efficacy remains unsatisfactory.Compared with these vaccine modalities,messager RNA(mRNA)-based vaccines offer technical and conceptional advances in personalized precise treatment,and thus represent a potentially cutting-edge option in novel therapeutic approaches for pancreatic cancer.This review summarizes the current progress on pancreatic cancer vaccines,highlights the superiority of mRNA vaccines over other conventional vaccines,and proposes the viable tactic for designing and applying personalized mRNA vaccines for the precise treatment of pancreatic cancer. 展开更多
关键词 Pancreatic cancer Precise therapy Cancer vaccine mRNA vaccine Tumor antigen Immune subtype
原文传递
mRNA vaccine development for cholangiocarcinoma:a precise pipeline
4
作者 Tian-Yu Tang Xing Huang +2 位作者 gang zhang Ming-Hao Lu Ting-Bo Liang 《Military Medical Research》 SCIE CAS CSCD 2023年第2期262-267,共6页
Cholangiocarcinoma(CHOL)is one of the most aggressive tumors worldwide and cannot be effectively treated by conventional and novel treatments,including immune checkpoint blockade therapy.The mRNA vaccine-based immunot... Cholangiocarcinoma(CHOL)is one of the most aggressive tumors worldwide and cannot be effectively treated by conventional and novel treatments,including immune checkpoint blockade therapy.The mRNA vaccine-based immunotherapeutic strategy has attracted much attention for various diseases,however,its application in CHOL is limited due to the thoughtlessness in the integration of vaccine design and patient selection.A recent study established an integrated path for identifying potent CHOL antigens for mRNA vaccine development and a precise stratification for identifying CHOL patients who can benefit from the mRNA vaccines.In spite of a promising prospect,further investigations should identify immunogenic antigens and onco-immunological characteristics of CHOL to guide the clinical application of CHOL mRNA vaccines in the future. 展开更多
关键词 Cholangiocarcinoma(CHOL) mRNA vaccine Tumor antigen Immune subtype Immune microenvironment
原文传递
Active learning accelerated Monte-Carlo simulation based on the modified K-nearest neighbors algorithm and its application to reliability estimations
5
作者 Zhifeng Xu Jiyin Cao +2 位作者 gang zhang Xuyong Chen Yushun Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期306-313,共8页
This paper proposes an active learning accelerated Monte-Carlo simulation method based on the modified K-nearest neighbors algorithm.The core idea of the proposed method is to judge whether or not the output of a rand... This paper proposes an active learning accelerated Monte-Carlo simulation method based on the modified K-nearest neighbors algorithm.The core idea of the proposed method is to judge whether or not the output of a random input point can be postulated through a classifier implemented through the modified K-nearest neighbors algorithm.Compared to other active learning methods resorting to experimental designs,the proposed method is characterized by employing Monte-Carlo simulation for sampling inputs and saving a large portion of the actual evaluations of outputs through an accurate classification,which is applicable for most structural reliability estimation problems.Moreover,the validity,efficiency,and accuracy of the proposed method are demonstrated numerically.In addition,the optimal value of K that maximizes the computational efficiency is studied.Finally,the proposed method is applied to the reliability estimation of the carbon fiber reinforced silicon carbide composite specimens subjected to random displacements,which further validates its practicability. 展开更多
关键词 Active learning Monte-carlo simulation K-nearest neighbors Reliability estimation CLASSIFICATION
下载PDF
Visualizing and witnessing first-order coherence,Bell nonlocality and purity by using a quantum steering ellipsoid in the non-inertial frame
6
作者 杨欢 邢玲玲 +3 位作者 杜明明 孔敏 张刚 叶柳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期210-218,共9页
A quantum steering ellipsoid(QSE)is a visual characterization for bipartite qubit systems,and it is also a novel avenue for describing and detecting quantum correlations.Herein,by using a QSE,we visualize and witness ... A quantum steering ellipsoid(QSE)is a visual characterization for bipartite qubit systems,and it is also a novel avenue for describing and detecting quantum correlations.Herein,by using a QSE,we visualize and witness the first-order coherence(FOC),Bell nonlocality(BN)and purity under non-inertial frames.Also,the collective influences of the depolarizing channel and the non-coherence-generating channel(NCGC)on the FOC,BN and purity are investigated in the QSE formalism.The results reveal that the distance from the center of the QSE to the center of the Bloch sphere visualizes the FOC of a bipartite system,the lengths of the QSE semiaxis visualize the BN,and the QSE's shape and position dominate the purity of the system.One can capture the FOC,BN and purity via the shape and position of the QSE in the non-inertial frame.The depolarizing channel(the NCGC)gives rise to the shrinking and degradation(the periodical oscillation)of the QSE.One can use these traits to visually characterize and detect the FOC,BN and purity under the influence of external noise.Of particular note is that the condition for the QSE to achieve the center of the Bloch sphere cannot be influenced by the depolarizing channel and the NCGC.The characterization shows that the conditions for the disappearance of the FOC are invariant under the additional influences of the depolarizing channel and NCGC. 展开更多
关键词 quantum steering ellipsoid first-order coherence Bell-nonlocality PURITY
原文传递
Subcellular Distribution and Chemical Forms of Cadmium in the Medicine Food Homology Plant Platycodon grandiflorum(Jacq.)A.DC.
7
作者 Jia An Xiang Wang +7 位作者 Yajiang Jing Jianping Huang Qilong Wang gang zhang Jing Gao Liang Peng Wenli Huang Yonggang Yan 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第5期1405-1420,共16页
Although Platycodon grandiflorum(Jacq.)A.DC.is a renowned medicine food homology plant,reports of excessive cadmium(Cd)levels are common,which affects its safety for clinical use and food consumption.To enable its Cd ... Although Platycodon grandiflorum(Jacq.)A.DC.is a renowned medicine food homology plant,reports of excessive cadmium(Cd)levels are common,which affects its safety for clinical use and food consumption.To enable its Cd levels to be regulated or reduced,it is necessary to first elucidate the mechanism of Cd uptake and accumulation in the plant,in addition to its detoxification mechanisms.This present study used inductively couple plasma-mass-spectrometry to analyze the subcellular distribution and chemical forms of Cd in different tissues of P.grandiflorum.The experimental results showed that Cd was mainly accumulated in the roots[predominantly in the cell wall(50.96%-61.42%)],and it was found primarily in hypomobile and hypotoxic forms.The proportion of Cd in the soluble fraction increased after Cd exposure,and the proportion of insoluble phosphate Cd and oxalate Cd increased in roots and leaves,with a higher increase in oxalate Cd.Therefore,it is likely that root retention mechanisms,cell wall deposition,vacuole sequestration,and the formation of low mobility and low toxicity forms are tolerance strategies for Cd detoxification used by P.grandiflorum.The results of this study provide a theoretical grounding for the study of Cd accumulation and detoxification mechanisms in P.grandiflorum,and they can be used as a reference for developing Cd limits and standards for other medicine food homology plants. 展开更多
关键词 CADMIUM Platycodon grandiflorum inductively coupled plasma-mass-spectrometry subcellular distribution chemical forms heavy metal tolerance medicine food homology
下载PDF
Identification of 1q21.1 microduplication in a family:A case report
8
作者 Ting-Ting Huang Hai-Feng Xu +7 位作者 Shang-Yu Wang Wen-Xin Lin Yie-Hen Tung Kaleem Ullah Khan Hui-Huizhang Hu Guo Guo Zheng gang zhang 《World Journal of Clinical Cases》 SCIE 2023年第4期874-882,共9页
BACKGROUND Copy number variation(CNV)has become widely recognized in recent years due to the extensive use of gene screening in developmental disorders and epilepsy research.1q21.1 microduplication syndrome is a rare ... BACKGROUND Copy number variation(CNV)has become widely recognized in recent years due to the extensive use of gene screening in developmental disorders and epilepsy research.1q21.1 microduplication syndrome is a rare CNV disease that can manifest as multiple congenital developmental disorders,autism spectrum disorders,congenital malformations,and congenital heart defects with genetic heterogeneity.CASE SUMMARY We reported a pediatric patient with 1q21.1 microduplication syndrome,and carried out a literature review to determine the correlation between 1q21.1microduplication and its phenotypes.We summarized the patient’s medical history and clinical symptoms,and extracted genomic DNA from the patient,her parents,elder brother,and sister.The patient was an 8-mo-old girl who was hospitalized for recurrent convulsions over a 2-mo period.Whole exon sequencing and whole genome low-depth sequencing(CNV-seq)were then performed.Whole exon sequencing detected a 1.58-Mb duplication in the CHR1:145883867-147465312 region,which was located in the 1q21.1 region.Family analysis showed that the pathogenetic duplication fragment,which was also detected in her elder brother’s DNA originated from the mother.CONCLUSION Whole exon sequencing combined with quantitative polymerase chain reaction can provide an accurate molecular diagnosis in children with 1q21.1 microduplication syndrome,which is of great significance for genetic counseling and early intervention. 展开更多
关键词 1q21.1 microduplication syndrome EPILEPSY Copy number variation FAMILIAL Whole exon sequencing Congenital developmental disorders Case report
下载PDF
De novo mutation of NAXE(APOAIBP)-related early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy-1:A case report
9
作者 Le Ding Ting-Ting Huang +8 位作者 Guo-Huan Ying Shang-Yu Wang Hai-Feng Xu Hao Qian Faiza Rahman Xiao-Peng Lu Hu Guo Guo Zheng gang zhang 《World Journal of Clinical Cases》 SCIE 2023年第14期3340-3350,共11页
BACKGROUND Early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy-1(PEBEL1)is a rare autosomal recessive severe neurometabolic disease.The aim of this study was to investigate the clinical ... BACKGROUND Early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy-1(PEBEL1)is a rare autosomal recessive severe neurometabolic disease.The aim of this study was to investigate the clinical characteristics and genetic pathogenicity of PEBEL1 caused by rare NAXE(or APOA1BP)-related defects.CASE SUMMARY The patient was a girl aged 2 years and 10 mo.She was hospitalized due to walking disorder for>40 d.The clinical manifestations were ataxia,motor function regression,hypotonia,and eyelid ptosis.Within 1 mo of hospitalization,she developed sigh breathing,respiratory failure,cerebellar edema and brain hernia,and finally she died.Changes were found in cranial imaging,including cerebellar edema accompanied by symmetrical myelopathy.Through whole exome sequencing,we detected NAXE compound heterozygous variation(NM 144772.3)c.733A>C(p.Lys245Gln,dbSNP:rs770023429)and novel variation c.370G>T(p.Gly124Cys)in the germline gene.The clinical features and core phenotypes of this case were consistent with 18 previously reported cases of PEBEL1.CONCLUSION This is the first case of NAXE-related PEBEL1 with severe clinical phenotype in China' Mainland.The p.Gly124Cys mutation discovered in this case has enriched the pathogenic variation spectrum of NAXE. 展开更多
关键词 ENCEPHALOPATHY Respiratory insufficiency Cerebral edema NAXE gene APOAIBP gene Novel variation Case report
下载PDF
Pressure-dependent electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X=Ca,Mg):A first-principles study
10
作者 Chunbao Feng Changhe Wu +8 位作者 Xin Luo Tao Hu Fanchuan Chen Shichang Li Shengnan Duan Wenjie Hou Dengfeng Li gang Tang gang zhang 《Journal of Semiconductors》 EI CAS CSCD 2023年第10期52-60,共9页
Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of... Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X^(2+)=Ca,Mg)upon compression by first-principles calculations.Our results reveal that the system is anisotropic,and the lat-tice constant a of X_(3)NP exhibits the fastest rate of decrease upon compression among the three directions,which is different from the typical Pnma phase of halide and chalcogenide perovskites.Meanwhile,Ca_(3)NP has higher compressibility than Mg_(3)NP due to its small bulk modulus.The electronic and optical properties of Mg_(3)NP show small fluctuations upon compression,but those of Ca_(3)NP are more sensitive to pressure due to its higher compressibility and lower unoccupied 3d orbital energy.For example,the band gap,lattice dielectric constant,and exciton binding energy of Ca_(3)NP decrease rapidly as the pressure increases.In addition,the increase in pressure significantly improves the optical absorption and theoretical conversion effi-ciency of Ca_(3)NP.Finally,the mechanical properties of X_(3)NP are also increased upon compression due to the reduction in bond length,while inducing a brittle-to-ductile transition.Our research provides theoretical guidance and insights for future experi-mental tuning of the physical properties of antiperovskite semiconductors by pressure. 展开更多
关键词 ANTIPEROVSKITE hydrostatic pressure physical properties first-principles calculations
下载PDF
Bilateral thigh pyomyositis in an otherwise healthy middle-aged woman:A case report
11
作者 Min Cui gang zhang +2 位作者 Na zhang Lei Han Zai-Qi Ma 《World Journal of Clinical Cases》 SCIE 2023年第25期5977-5981,共5页
BACKGROUND Pyomyositis generally occurs in otherwise healthy young men.Because this condition is unusual among otherwise healthy women in temperate climates,we present the following case.CASE SUMMARY An otherwise heal... BACKGROUND Pyomyositis generally occurs in otherwise healthy young men.Because this condition is unusual among otherwise healthy women in temperate climates,we present the following case.CASE SUMMARY An otherwise healthy 43-year-old woman presented with bilateral pain in her lower extremities and fever.Magnetic resonance imaging(MRI)findings were indicative of myositis with a possible abscess.We initiated empirical antibiotic therapy with ceftriaxone.However,the swelling and pain in her legs persisted even after 7 d of treatment.Contrast MRI revealed multiple pockets of pus in the vastus lateralis and gluteal muscles.We performed needle aspiration of these abscesses with ultrasound guidance and local anesthesia.Upon culturing,the purulent material was positive for Staphylococcus aureus.We diagnosed her with S.aureus-induced pyomyositis of the vastus lateralis muscle and gluteus region.Based on the antibiotic sensitivity report,ceftriaxone was administered for an additional 7 d.By day 15 post-drainage,the patient was able to start walking.Oral antibiotic therapy was continued for 1 wk following her discharge from hospital,after which her symptoms resolved completely.CONCLUSION Pyomyositis may present with muscle pain,swelling,and fever.Ultrasoundguided percutaneous puncture and drainage may enable timely diagnosis and treatment. 展开更多
关键词 Pyomyositis Endoscopic ultrasound-guided fine-needle aspiration Staphylococcus aureus Climate Magnetic resonance imaging Case report
下载PDF
Review of Black Start on New Power System Based on Energy Storage Technology
12
作者 Jin Fan Litao Niu +8 位作者 Cuiping Li gang zhang He Li Yiming Wang Junhui Li Qinglong Song Jiacheng Sun Jianglong Pan Fangfang Lai 《Energy Engineering》 EI 2023年第12期2857-2878,共22页
With the continuous development of new energy generation technology and the increasingly complex power grid environment,the traditional black start scheme cannot meet the requirements of today’s power grid in order t... With the continuous development of new energy generation technology and the increasingly complex power grid environment,the traditional black start scheme cannot meet the requirements of today’s power grid in order to ensure the stable operation of the power system can be restored quickly in the face of large power outages,so a more complete black start scheme needs to be developed to cope with the new power system.With the development of energy storage technology,the limitations of the traditional black-start scheme can be solved by new energy farms with energy storage configuration.Therefore,this paper investigates the problems faced by black-start,the key technologies of energy storage assisted new energy black-start,and introduces the research related to new energy black-start technology to provide reference for future research and application of new energy black-start. 展开更多
关键词 New energy black start energy storage rapid recovery
下载PDF
Effects of Polygonatum odoratum Polysaccharide on Reproductive Hormones in Male Rats Fed a High-fat Diet
13
作者 Yixin YAN gang zhang +5 位作者 Lingli BAI Xin TANG Mengjun YUAN Yihong HU Yan WANG Chenzhong JIN 《Agricultural Biotechnology》 CAS 2023年第2期54-58,共5页
[Objectives]This study was conducted to investigate the effects of Polygonatum odoratum polysaccharide(POP)on organ relative weights and reproductive hormone levels in male rats fed a high-fat diet.[Methods]Thirty hea... [Objectives]This study was conducted to investigate the effects of Polygonatum odoratum polysaccharide(POP)on organ relative weights and reproductive hormone levels in male rats fed a high-fat diet.[Methods]Thirty healthy male Sprague-Dawley(SD)rats were randomly divided into two groups according to their body weight:10 in normal control group(Group NC,n=10)and 20 in experimental group(n=20).The rats in experimental group were fed a high-fat diet for eight weeks before they were further randomly divided into two groups:high fat group(Group HF)and high fat+400 mg/(kg·d)POP group(Group HF+POP).In Group HF+POP,the rats were administered with POP for another six weeks,before their blood plasma was collected,and the relative weights of their testis and epididymis were calculated.The plasma levels of testosterone(T),estrogen(E2),follicle-stimulating hormone(FSH),cortisol(C)and luteinizing hormone(LH)were measured by radioimmunoassay,and the plasma levels of sex hormone-binding globulin(SHBG)and insulin-like growth factor-1(IGF-1)were determined by enzyme-linked immunosorbent assay.[Results]Compared with Group HF,POP could effectively inhibit rat obesity caused by high-fat diets,increase the relative weights of their testis and epididymis,plasma levels of LH,E2,FSH,T,SHBG and IGF-1,and reduce the plasma level of E2.[Conclusions]Polygonatum odoratum polysaccharide(POP)is able to effectively regulate the level of reproductive hormones in high-fat diet fed rats,and helps to protect their reproductive function. 展开更多
关键词 Polygonatum odoratum polysaccharide High-fat diet Reproductive hormones OBESITY SD rats
下载PDF
2022年高考数学文化试题的特点分析
14
作者 张刚 《河北理科教学研究》 2023年第4期58-62,共5页
文章以高考评价体系为依据,对2022年新高考数学文化试题,从试题考查背景、文化价值、高考评价载体以及创新特色等方面进行评析,由此引发教学上的一些启示.给高考复习带来一些备考建议,希望真正落实高考评价体系,提升数学文化价值.
关键词 高考评价体系 数学文化 试题评析 备考建议
下载PDF
高熔体流动性聚芳酯的合成及性能 被引量:3
15
作者 张雨 严光明 +1 位作者 张刚 杨杰 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第5期161-166,共6页
通过相转移界面缩聚的方法,将4,4’-二乙基-1,1’-二苯基苯酚(BHPP)和2,2-双(4-羟基苯基)丙烷(BP A)、对苯二甲酰氯(TPC)以及间苯二甲酰氯(IPC)进行共聚,合成了一系列不同酰氯比例的含乙基侧基的聚芳酯(PABAs)。利用核磁共振和傅里叶变... 通过相转移界面缩聚的方法,将4,4’-二乙基-1,1’-二苯基苯酚(BHPP)和2,2-双(4-羟基苯基)丙烷(BP A)、对苯二甲酰氯(TPC)以及间苯二甲酰氯(IPC)进行共聚,合成了一系列不同酰氯比例的含乙基侧基的聚芳酯(PABAs)。利用核磁共振和傅里叶变换红外光谱对BHPP单体及PABA系列聚芳酯的结构进行了表征。差示扫描量热法和热重分析结果表明,聚合物具有良好的热性能,其玻璃化转变温度(Tg)为183.7~209.9℃,初始分解温度高于436℃。拉伸测试结果表明聚合物薄膜的拉伸强度大于60 MPa,力学性能优异。同时通过流变测试表明所得聚芳酯具有优良的熔体流动性,乙基侧基的引入使其熔融加工性能得到较大提升。 展开更多
关键词 环己基 聚芳酯 界面缩聚
下载PDF
Determination of the available energy values and amino acid digestibility of Flammulina velutipes stem waste and its effects on carcass trait and meat quality fed to growing-finishing pigs 被引量:6
16
作者 Xuzhou Liu Bo zhang +7 位作者 Hansuo Liu gang zhang Jinbiao Zhao Ling Liu Xiangshu Piao Hui Song Shuai zhang Yu Li 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期747-766,共20页
Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate... Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate the effects of dietary FVS inclusion on growth performance,biochemical profile of serum,fecal short chain fatty acid(SCFA)concentration,carcass traits,meat quality,intestinal morphology and microflora of pigs.In Exp.1,twelve crossbred barrows with initial body weight(IBW)of 37.48±4.31 kg were randomly allotted to 2 dietary treatments,including a corn basal diet and an experimental diet containing 24.35%FVS.In Exp.2,twelve barrows fitted with an ileal T-cannula(IBW:32.56±1.67 kg)were randomly allotted to 2 dietary treatments,which included a N-free diet and an experimental diet containing 40.0%FVS.In Exp.3,ninety growing pigs(IBW:63.98±6.89 kg)were allotted to 1 of 3 treatment diets for 63 d,including a basal diet and 2 experimental diets with 2.5%and 5%FVS,respectively.Results:The digestible energy(DE)and metabolizable energy(ME)of FVS were 4.58 and 4.06 MJ/kg on dry matter basis,respectively,and the standardized ileal digestibility(SID)of indispensable AAs ranged from 17.50%to 59.47%.Pigs fed diets with 2.5%FVS showed no difference on average daily gain(ADG)and gain to feed ratio(G/F).Although dietary 5%FVS inclusion impaired apparent total tract digestibility(ATTD)of organic matter and gross energy,it elevated the SCFA concentration(P≤0.04)in gut and antioxidant capacity in serum.In addition,dietary FVS inclusion depressed the backfat thickness(P=0.03)in pigs.The longissimus dorsi muscle of pigs fed FVS revealed higher n-3 polyunsaturated fatty acid concentration and optimized fatty acid composition.Dietary 2.5%FVS inclusion also improved the intestinal development and health by increasing the villius height to crypt depth ratio(V/C)in jejunum(P<0.01),and promoting microbial diversity and beneficial microbiota proliferation.Conclusions:It is feasible to include moderate content of FVS as an unconventional fiber ingredient in diet of growingfinishing pigs. 展开更多
关键词 Amino acid DIGESTIBILITY Available energy Fiber Flammulina velutipes STEM WASTE Growing-finishing PIGS Growth performance MEAT quality
下载PDF
Analysis of an improved acquisition method for high-dynamic BOC signal 被引量:5
17
作者 Yi Pan Tianqi zhang +1 位作者 gang zhang Zhongtao Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第6期1158-1167,共10页
To reach a compromise between short acquisition time and excellent detection probability for the high-dynamic binary offset carrier(BOC) signal, an overall algorithm based on discrete polynomial-phase transform(DPT) a... To reach a compromise between short acquisition time and excellent detection probability for the high-dynamic binary offset carrier(BOC) signal, an overall algorithm based on discrete polynomial-phase transform(DPT) and partial matching filter(PMF)-fast Fourier transform(FFT) algorithm is given. The high order items of received signals are removed by the method of DPT,and the PMF-FFT algorithm is redesigned for the BOC signal.The simulation experiments and theoretical analyses verify that the improved algorithm has attained improvement in acquisition performance. 展开更多
关键词 acquisition high-dynamic binary OFFSET carrier (BOC) signal discrete polynomial-phase TRANSFORM (DPT) partial matching filter (PMF)-fast Fourier TRANSFORM (FFT)
下载PDF
基于离子液体的超级电容在3 V及65℃老化条件下的铝碳界面效应
18
作者 叶珍珍 张抒婷 +7 位作者 陈鑫祺 王瑾 金鹰 崔超婕 张磊 钱陆明 张刚 骞伟中 《电化学》 CAS CSCD 北大核心 2022年第12期50-59,共10页
相比于传统乙腈电解液体系的超级电容器,离子液体基超级电容器具有工作窗口电压高,能量密度大,不可燃等优点,适用于碳中和时代清洁但不稳定电力领域的大规模储能。然而,目前的工作主要集中在对纽扣型离子液体-超级电容器的研究上,有关... 相比于传统乙腈电解液体系的超级电容器,离子液体基超级电容器具有工作窗口电压高,能量密度大,不可燃等优点,适用于碳中和时代清洁但不稳定电力领域的大规模储能。然而,目前的工作主要集中在对纽扣型离子液体-超级电容器的研究上,有关软包式离子液体-超级电容器的长循环寿命评测的报道较少。构建可靠的超级电容器用于长时间测试或在高温下开展加速老化测试,应考虑集流体/电极界面的良好接触,以最小化电荷转移电阻。本文以包覆不同碳层的泡沫铝为集流体,研究了超级电容器新系统中的碳-铝界面效应。通过环氧树脂薄膜碳化得到的均匀无定形碳层,相比通过PVDF粘附石墨烯碳层,赋予了铝相和碳相更强的相互作用。此外,为了充分挖掘大离子尺寸的离子液体电解液的潜力,本文采用介孔碳电极实现离子在介孔间的快速扩散。因此,本工作首次制备了由介孔碳电极、离子液体电解液和覆碳三维泡沫铝集流体组成的新结构软包式超级电容器。以自制的容量为37 F的不同软包式超级电容器件,通过3 V、65℃、500 h加速老化试验,研究了其时间依赖性的电化学性能,包括CV测试、恒流充放电测试、电容值、接触电阻、电化学阻抗谱等。相比石墨烯包覆的泡沫铝基器件,无定形碳层包覆的泡沫铝基器件表现出更高的电容保持率。此外,我们还对ESR进行了等效电路拟合,并深入分析了接触电阻、电荷转移电阻、韦伯电阻,研究了C-Al界面对高能量密度超级电容器的高性能和稳定性的影响。500小时老化测试前后的极片表征证实了上述结果。高温、高压条件使粘附石墨烯碳层的泡沫铝界面结构不可靠。而泡沫铝表面原位包覆的碳层在老化过程中表现出较强的相互作用和稳定的结构。这些坚实的数据为面向高能量密度、高功率密度和长循环寿命,进一步优化高窗口电压超级电容器提供了充足的信息。 展开更多
关键词 超级电容器 老化试验 碳-铝界面 离子液体 泡沫铝
下载PDF
模拟废旧锂离子电池湿法冶金浸出液再生铝掺杂LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)正极材料 被引量:6
19
作者 李芳成 张刚 +4 位作者 张宗良 杨健 刘芳洋 贾明 蒋良兴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期593-603,共11页
采用共沉淀法制备均相Al掺杂的LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)正极材料,以利用Al对再生镍钴锰(NCM)正极材料的正面改性作用,并改善锂离子电池回收过程中繁琐和高成本的除杂过程。当浸出液中的Al^(3+)含量为过渡金属(Ni、Co和Mn)总量的... 采用共沉淀法制备均相Al掺杂的LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)正极材料,以利用Al对再生镍钴锰(NCM)正极材料的正面改性作用,并改善锂离子电池回收过程中繁琐和高成本的除杂过程。当浸出液中的Al^(3+)含量为过渡金属(Ni、Co和Mn)总量的1%(摩尔分数)时,制备的Al掺杂NCM正极材料中晶格氧和Ni^(2+)的浓度增加。在0.1C下的初始比容量为167.4 mA·h/g,在1C下循环400次后容量保持率为79.1%。此外,这种Al掺杂样品具有更高的倍率性能和更小的电化学阻抗。这些发现为工业上通过掺入锂离子电池回收过程中产生的Al^(3+)杂质,重新合成具有更好电化学性能的正极材料的工艺开发提供了参考。 展开更多
关键词 废旧锂离子电池 再生 铝掺杂 三元正极材料 共沉淀
下载PDF
Theory Study and Application of the BP-ANN Method for Power Grid Short-Term Load Forecasting 被引量:12
20
作者 Xia Hua gang zhang +1 位作者 Jiawei Yang Zhengyuan Li 《ZTE Communications》 2015年第3期2-5,共4页
Aiming at the low accuracy problem of power system short-term load forecasting by traditional methods,a back-propagation artificial neural network(BP-ANN) based method for short-term load forecasting is presented in t... Aiming at the low accuracy problem of power system short-term load forecasting by traditional methods,a back-propagation artificial neural network(BP-ANN) based method for short-term load forecasting is presented in this paper.The forecast points are related to prophase adjacent data as well as the periodical long-term historical load data.Then the short-term load forecasting model of Shanxi Power Grid(China) based on BP-ANN method and correlation analysis is established.The simulation model matches well with practical power system load,indicating the BP-ANN method is simple and with higher precision and practicality. 展开更多
关键词 短期负荷预测方法 人工神经网络方法 山西电网 短期负荷预测模型 应用 预测精度 电力系统 传统方法
下载PDF
上一页 1 2 5 下一页 到第
使用帮助 返回顶部