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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao gang zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP Improved methods Field application cases
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Intersection of two rare conditions:Clinical reflection on tuberous sclerosis combined with primary lymphedema
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作者 Xiao Wu Xiao-Hui Min +2 位作者 Hai-Feng Xu M Jalal Ud Din gang zhang 《World Journal of Clinical Cases》 SCIE 2025年第7期13-16,共4页
This editorial discusses a case report recently published in the World Journal of Clinical Cases.The report describes the clinical presentation,imaging,diagnosis,and treatment of a patient with tuberous sclerosis comp... This editorial discusses a case report recently published in the World Journal of Clinical Cases.The report describes the clinical presentation,imaging,diagnosis,and treatment of a patient with tuberous sclerosis complex(TSC)combined with primary lymphedema(PLE).Additionally,it retrospectively analyzes the data of 16 previously reported cases of children with TSC combined with PLE to summarize the epidemiology,genetic diagnosis,and current main treatments of these patients.The report also speculates on the pathological and physiological mechanisms underlying TSC combined with PLE.TSC combined with PLE is rare;therefore,the report provides a theoretical basis for understanding the pathophysiological mechanisms and treatment options for patients with TSC and PLE.Comprehensive clinical management of TSC is essential due to the diverse and multiorgan nature of its manifestations,often requiring a multidisciplinary approach for newly diagnosed cases. 展开更多
关键词 Tuberous sclerosis complex LYMPHEDEMA EXAMINATION Diagnosis Treatment
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Atomic Mass Engineering of Ultra-High Thermal Conductivity in Large Bandgap Materials:A Case Study with Boron Arsenide
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作者 Tingting Wang Xiaozhe Li +4 位作者 Zhuo Ju gang zhang Dengke Ma Wu Li Lifa zhang 《Chinese Physics Letters》 2025年第7期454-466,共13页
Heat dissipation highly relies on the thermal conductivity(κ)of materials.Materials with large bandgaps and signifcant atomic mass ratios,such as BAs,SiC,andθ-TaN,have attracted considerable attention due to their p... Heat dissipation highly relies on the thermal conductivity(κ)of materials.Materials with large bandgaps and signifcant atomic mass ratios,such as BAs,SiC,andθ-TaN,have attracted considerable attention due to their potential for achieving ultra-highκ,with BAs serving as a particularly representative example due to its unique combination of large bandgap and high thermal conductivity.In this paper,the efects of atomic mass modifcation on phonon bandgap andκare systematically investigated using a BAs model,accounting for both three-and four-phonon scattering processes.A 20%increase inκcan be obtained by substituting B,achieved through widening the phonon bandgap,which suppresses phonon scattering.Notably,the AAOO four-phonon scattering channel is more suppressed than the AAO three-phonon channel,leading to an increased phonon lifetime(τ).For As,κcan also be enhanced by 5%when replaced by lighter atoms,such as^(69)As,primarily due to the increased phonon group velocity(υ).We systematically clarify how atomic-mass-induced bandgap variations afectτ,υ,and thereforeκin wide-bandgap systems.Our work provides a specifc scheme for further improving the ultra-highκof materials with large bandgaps,which possesses great guiding signifcance. 展开更多
关键词 phonon bandgap phonon lifetime phonon scattering thermal conductivity atomic mass modifcation group velocity atomic mass engineering heat dissipation
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Room Temperature Thermal Switching Based on Monolayer Boron Nitride
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作者 Dingbo zhang Ke Wang +2 位作者 Shuai Chen Yuxiang Ni gang zhang 《Chinese Physics Letters》 2025年第9期102-125,共24页
The research on materials capable of manipulating thermal conductivity continues to fuel the development of thermal controlling devices.Here,using ab initio calculations and the Boltzmann transport equation,we demonst... The research on materials capable of manipulating thermal conductivity continues to fuel the development of thermal controlling devices.Here,using ab initio calculations and the Boltzmann transport equation,we demonstrate that the thermal conductivity of semi-fluorinated hexagonal boron nitride(h-BN)can be reversibly manipulated at 300 K,and the ratio for the regulation of thermal conductivity reaches up to 11.23.Such behavior originates from the high sensitivity of thermal conductivity to magnetic ordering.Semi-fluorinated h-BN is a paramagnetic material at room temperature due to its Curie temperature of 270 K.Impressively,semi-fluorinated h-BN can be modulated into a ferromagnetic system by adding an external magnetic field of 11.15 T,resulting in greatly and reversibly tunable thermal conductivity at room temperature.Furthermore,in-depth analyses of phonon properties show that compared with the paramagnetic phase,both ferromagnetic and antiferromagnetic semi-fluorinated h-BN significantly reduce phonon scattering and anharmonicity,thereby enhancing thermal conductivity.The results qualify semi-fluorinated h-BN as a potential candidate for thermal switching applications at room temperature. 展开更多
关键词 ab initio calculations boltzmann transport equationwe thermal controlling deviceshereusing thermal conductivity regulation thermal conductivity magnetic ordering manipulating thermal conductivity semi fluorinated hexagonal boron nitride
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Study on the effect and mechanism of Taohe Chengqi Decoction on relieving vascular endothelial injury caused by heat and blood stasis syndrome
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作者 Yuan-Rong Zou Jian-Ping Huang +7 位作者 Ze-Bing Xia Yan-Chen Wang Zi-Jian zhang Liang Peng gang zhang Jing Gao Yong-gang Yan Hong-Yan Wang 《Traditional Medicine Research》 2025年第12期1-15,共15页
Background:Heat and Blood Stasis Syndrome(HBSS),a syndrome in traditional Chinese medicine is intrinsically linked to vascular endothelial injury.Taohe Chengqi Decoction(THCQT)is considered to treat diseases related t... Background:Heat and Blood Stasis Syndrome(HBSS),a syndrome in traditional Chinese medicine is intrinsically linked to vascular endothelial injury.Taohe Chengqi Decoction(THCQT)is considered to treat diseases related to HBSS by improving inflammatory response,oxidative stress,and blood circulation disorder.This study aimed to elucidate the therapeutic effects and underlying mechanisms of THCQT on vascular endothelial injury induced by HBSS.Methods:LC-MS/MS was used to analyze the chemical components of THCQT.The intervention involved administering saline and appropriate drugs to rats via gavage for 21 days,followed by 24-h repeated tail vein injections of LPS to replicate the HBSS model.Pharmacodynamic assessments included measuring rat body temperature,hemorheology,coagulation function,fever mediators,inflammatory factors,vascular endothelial injury factors,and aortic histopathology to evaluate the preventive effect of THCQT on vascular endothelial injury caused by HBSS.Additionally,proteomics and transcriptomics analyses elucidated THCQT’s impact on mRNA and protein expression levels,further validated by quantitative real-time PCR and Western blot analysis.Results:THCQT was detected to contain 293 chemical components,and some active ingredients with high levels have anti-inflammatory,antioxidant,and inhibiting platelet aggregation properties.Pharmacodynamic results demonstrated that H-THCQT significantly suppressed the elevation of body temperature and downregulated TNF-α,cAMP,and PGE2 expression levels.Additionally,it attenuated the increase in WBV and PV,and prolonged APTT,PT,and TT.It enhanced the expression of NO and PGI2 in plasma,inhibiting ET-1 and TXA2 expression,thus ameliorating aortic pathological injury.Combined transcriptomics and proteomics analyses of the KEGG pathway suggest that the MAPK pathway is crucial in mitigating vascular endothelial injury induced by HBSS through THCQT administration.Furthermore,quantitative real-time PCR and Western blot analyses of the aorta indicated that THCQT inhibits the mRNA and protein phosphorylation levels of p38MAPK,ERK,and JNK in the MAPK signaling pathway of HBSS rats.Conclusion:Our work not only helps explore the common mechanism of THCQT in treating multi-system diseases induced by vascular endothelial injury due to HBSS but also provides a valuable research method for investigating the mechanisms underlying traditional Chinese medicine syndromes. 展开更多
关键词 Taohe Chengqi Decoction heat and blood stasis syndrome vascular endothelial injury TRANSCRIPTOMIC PROTEOMIC MAPK signal pathway
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Exploring the mechanism of action of Huangqin Shegan Decoction in the treatment of acute pneumonia based on network pharmacology combined with transcriptomics
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作者 Ze-Bing Xia Yuan-Rong Zou +8 位作者 Yan-Chen Wang Zi-Jian zhang gang zhang Liang Peng Jing Gao Chang-Li Wang Jun-Ming Zheng Hong-Yan Wang Yong-gang Yan 《Traditional Medicine Research》 2025年第7期15-28,共14页
Background:In this research,we explored the operational principles of Huangqin Shegan decoction(HQSGD)for addressing acute pneumonia utilizing network pharmacology(NP)and transcriptomic analysis.Methods:Methods:A rat ... Background:In this research,we explored the operational principles of Huangqin Shegan decoction(HQSGD)for addressing acute pneumonia utilizing network pharmacology(NP)and transcriptomic analysis.Methods:Methods:A rat model of acute pneumonia was developed by treating rats with lipopolysaccharide(LPS)through a non-exposed tracheal drip.The pharmacological effects of HQSGD were evaluated via histopathological analysis of rat lung tissues,histological scoring of lung injury,assessment of lung index,serum inflammatory factors,oxidative stress levels,western blotting,and qRT-PCR.The active compounds of HQSGD were detected utilizing ultra-performance liquid chromatography coupled with tandem mass spectrometry(UPLC-MS/MS).NP and transcriptomic analysis were integrated to determine signaling pathways implicated in the pharmacological activity of HQSGD.The expression levels of mRNA and protein for factors implicated in these pathways were evaluated in rat lung tissues via qRT-PCR and western blotting,respectively.Results:HQSGD alleviated acute pneumonia in rats by reducing the lung index and the levels of TNF-α,IL-1β,CRP,and MDA while increasing the levels of SOD.The UPLC-MS/MS and NP techniques facilitated the identification of 28 bioactive constituents present in HQSGD.The principal 20 KEGG pathways were identified by intersecting the targets of HQSGD with pneumonia-related targets.These pathways were screened by comparing the transcriptomic data of the blank and model cohorts and those of the model and drug administration cohorts.GO and KEGG analyses indicated that the PI3K/AKT/NF-κB pathway was a potentially effective target of HQSGD.Conclusion:This investigation revealed the overall multi-component,multi-target,and multi-pathway interactions of HQSGD in the treatment of acute pneumonia. 展开更多
关键词 Huangqin Shegan Decoction LPS acute pneumonia network pharmacology TRANSCRIPTOMICS
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Solidification cracking restraining mechanism of laser-welded aluminum alloy joints using power modulation technique
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作者 Jing HAN Yu SHI +4 位作者 gang zhang You-wei XU Volodymyr KORZHYK Wang-yun LE Feng-xian DAI 《Transactions of Nonferrous Metals Society of China》 2025年第8期2521-2535,共15页
The 7075 aluminum alloy was subjected to power-modulated laser welding using a full-domain power modulation(FDPM)laser oscillating welding system.Three different power modes were utilized:constant power(CP),gradient p... The 7075 aluminum alloy was subjected to power-modulated laser welding using a full-domain power modulation(FDPM)laser oscillating welding system.Three different power modes were utilized:constant power(CP),gradient power(GP),and alternating power(AP)modes.The impact of different power modes on joint crack sensitivity,microstructure,and residual stress was assessed.The results demonstrate that joint welded with the AP mode exhibits the lowest sensitivity to solidification cracking(with mean crack sensitivity of 18.3%),and the smallest average grain size in the fusion zone of the weld seam(80μm).Additionally,it shows the highest microhardness(HV 113)and the narrowest softening region(3.5 cm).Furthermore,the joint displays the lowest residual stress and cooling rate,which is the reason for its minimal crack sensitivity. 展开更多
关键词 aluminum alloy laser welding OSCILLATING crack sensitivity power modulation
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Interfacial design and thermoelectric properties of C_(3)N_(4)-C_(20) molecular junctions based on quantum interference
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作者 Shutao Hu Meng Qian +1 位作者 gang zhang Bei zhang 《Chinese Physics B》 2025年第6期109-115,共7页
Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an ef... Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an effective approach to suppress phonon thermal conductance. The thermoelectric properties of pure C_(3)N_(4) nanoribbon devices and C_(3)N_(4)-C_(20) molecular junctions are systematically investigated based on density functional theory(DFT) combined with nonequilibrium Green's function(NEGF) formalism. The results show that pure C_(3)N_(4) nanoribbon devices have superior charge transport capabilities and excellent Seebeck coefficients. A remarkable thermoelectric figure of merit(ZT = 0.98)is achieved near 0.09 e V. The pronounced scattering effect induced by embedding a C_(20) molecule in the center of the C_(3)N_(4) nanoribbon significantly suppresses phonon transport. A maximum ZT value of 1.68 is observed at 0.987 e V. The electron mobility of C_(3)N_(4)-C_(20)-par is effectively increased due to quantum interference effect which greatly improves the alignment between the C_(20) molecule's frontier orbital energy level and C_(3)N_(4) electrodes. The C_(3)N_(4)-C_(20)-van der Waals(vd W) molecular junction allows very few phonons to pass through the C_(20) molecule from the left electrode to the right electrode. As a result, the C_(3)N_(4)-C_(20)-vd W junction achieves an excellent ZT value of 3.82 near the Femi level. 展开更多
关键词 quantum interference effect C_(3)N_(4)-C_(20)molecular junctions thermoelectric properties first-principles theory
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Investigating maximal steered coherence under the common impacts of reservoir and noise
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作者 Ling-Ling Xing Huan Yang gang zhang 《Chinese Physics B》 2025年第5期230-235,共6页
Maximal steered coherence(MSC)is a noteworthy resource measure in the field of quantum information,and it is defined under the framework of coherence measure and the formalism of quantum steering ellipsoids(QSEs).Here... Maximal steered coherence(MSC)is a noteworthy resource measure in the field of quantum information,and it is defined under the framework of coherence measure and the formalism of quantum steering ellipsoids(QSEs).Here,we explore the MSC of a two-qubit X state under the common influences of reservoir and noise.The results disclose that the introduction of auxiliary qubits can give rise to enhancement of the MSC in both the strong and weak coupling regimes.Moreover,more auxiliary qubits can decrease the oscillation period of the MSC,and also suppress the oscillation amplitude of the MSC in the strong coupling regime.In contrast,the increases in auxiliary qubits result in the oscillation of the MSC for the setting of the initially weak coupling regime.Of particular interest is that the improvement effects of more auxiliary qubits on the MSC in the initially weak coupling regime are significantly stronger than that in the initially strong coupling regime. 展开更多
关键词 maximal steered coherence quantum steering ellipsoid RESERVOIR noise
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Hyperparameter optimization and force error correction of neuroevolution potential for predicting thermal conductivity of wurtzite GaN
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作者 Zhuo Chen Yuejin Yuan +3 位作者 Wenyang Ding Shouhang Li Meng An gang zhang 《Chinese Physics B》 2025年第8期157-164,共8页
As a representative of wide-bandgap semiconductors,wurtzite gallium nitride(GaN)has been widely utilized in highpower devices due to its high breakdown voltage and low specific on-resistance.Accurate prediction of wur... As a representative of wide-bandgap semiconductors,wurtzite gallium nitride(GaN)has been widely utilized in highpower devices due to its high breakdown voltage and low specific on-resistance.Accurate prediction of wurtzite GaN’s thermal conductivity is a prerequisite for designing effective thermal management systems for electronic applications.Machine learning-driven molecular dynamics simulation offers a promising approach to predicting the thermal conductivity of large-scale systems without requiring predefined parameters.However,these methods often underestimate the thermal conductivity of materials with inherently high thermal conductivity due to the large predicted force error compared with first-principles calculations,posing a critical challenge for their broader application.In this study,we successfully developed a neuroevolution potential for wurtzite GaN and accurately predicted its thermal conductivity,259±6 W/(m·K)at room temperature,achieving excellent agreement with reported experimental measurements.The hyperparameters of the neuroevolution potential(NEP)were optimized based on a systematic analysis of reproduced energy and force,structural features,and computational efficiency.Furthermore,a force error correction method was implemented,effectively reducing the error caused by the additional force noise in the Langevin thermostat by extrapolating to the zero-force error limit.This study provides valuable insights and holds significant implications for advancing efficient thermal management technologies in wide-bandgap semiconductor devices. 展开更多
关键词 machine learning potential molecular dynamics thermal conductivity gallium nitride
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基于文献计量学BSA在作物育种领域的应用现状与展望 被引量:6
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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
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例析奇偶分析法在数列前n项和中的求解策略
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作者 张刚 《河北理科教学研究》 2025年第2期1-5,8,共6页
在数列求和问题中,我们可以根据数列的结构特点,进行必要的奇偶项分析.文中借助几个典型问题,剖析了这类数列前n项和问题的几种求解策略.
关键词 奇偶分析 数列前N项和 求解策略
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高熔体流动性聚芳酯的合成及性能 被引量:3
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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
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基于蛾类多样性研究人工林斑块的边缘效应 被引量:6
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作者 段曼微 李香 +6 位作者 周阳 赵敏欣 孙秀玲 韩冰 张刚 权子豪 李凯 《生物多样性》 CAS CSCD 北大核心 2023年第5期65-75,共11页
斑块状造林是当前国内营建人工林的主要方式之一,在林内不同斑块间形成了大量的边缘环境。为探究人工林斑块间边缘效应的生物多样性特点,本文基于北京平原造林中的毛白杨(Populus tomentosa)林–国槐(Styphnolobium japonicum)林、国槐... 斑块状造林是当前国内营建人工林的主要方式之一,在林内不同斑块间形成了大量的边缘环境。为探究人工林斑块间边缘效应的生物多样性特点,本文基于北京平原造林中的毛白杨(Populus tomentosa)林–国槐(Styphnolobium japonicum)林、国槐林–栾树(Koelreuteria paniculata)林、栾树林–桧柏(Juniperus chinensis)林、旱柳(Salix matsudana)林–杜仲(Eucommia ulmoides)林4种树种组合,选择与植物具有营养关系的蛾类为研究对象,采用非度量多维尺度(NMDS)排序、Anosim分析、物种多样性指数等对蛾类数量、物种组成与多样性进行分析;并基于林下植被特征因子调查,使用Pearson相关性分析探讨了植被特征因子与蛾类群落特征的关系。结果表明:本研究共采集到蛾类4,428只,分属于24科144种。(1)斑块边缘的蛾类物种组成与斑块内存在差异,边缘独有种比例占所在样地组合物种数的13.59%–18.32%。(2)边缘物种多样性指数多为相邻斑块中间值或略高于斑块内;旱柳林–杜仲林边缘的Simpson指数显著高于杜仲林斑块,Shannon-Wiener多样性指数、Margalef丰富度指数显著高于旱柳林斑块,Pielou均匀度指数显著低于杜仲林斑块。(3)蛾类Simpson指数与植被的平均高度和平均盖度呈显著负相关关系;而蛾类物种数与植被的平均高度和平均盖度呈显著正相关关系。(4) 4种边缘类型的边缘效应均呈正效应(IH′>1),其中旱柳林–杜仲林边缘的边缘效应强度最低(IC=0.915185808)。斑块状人工林的边缘中存在对生境变化产生响应的蛾类类群,这是斑块状人工林生物多样性提高的基础。不同树种组合斑块的边缘效应所呈现的生物多样性特点不同,可能存在优势物种暴发的风险。本研究可为后续造林及林分管理提供指导意见。 展开更多
关键词 蛾类 边缘效应 人工林 生物多样性 斑块
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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:8
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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
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Regeneration of Al-doped LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathode material by simulated hydrometallurgy leachate of spent lithium-ion batteries 被引量:12
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作者 Fang-cheng LI gang zhang +4 位作者 Zong-liang zhang Jian YANG Fang-yang LIU Ming JIA Liang-xing JIANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期593-603,共11页
A uniform Al-doped LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathode material was prepared using a coprecipitation method to take advantage of the positive effect of Al on regenerated NCM(Ni,Co,Mn)cathode materials and ameliora... A uniform Al-doped LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathode material was prepared using a coprecipitation method to take advantage of the positive effect of Al on regenerated NCM(Ni,Co,Mn)cathode materials and ameliorate cumbersome and high-cost impurity removal processes during lithium-ion battery recycling.When the Al^(3+) content in the leachate was 1 at.%with respect to the total amount of transition metals(Ni,Co,and Mn),the produced Al-doped NCM cathode material increased concentrations of lattice oxygen and Ni^(2+).The initial specific capacity at 0.1C was 167.4 mA·h/g,with a capacity retention of 79.1%after 400 cycles at 1C.Further,this Al-doped sample showed improved rate performance and a smaller electrochemical impedance.These findings provide a reference for developing industrial processes to resynthesize cathode materials with improved electrochemical performance by incorporating Al^(3+) impurities produced during lithium-ion battery recycling. 展开更多
关键词 spent lithium-ion battery REGENERATION Al doping ternary cathode material coprecipitation
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大剂量呋塞米持续静脉泵入治疗老年重度心力衰竭患者的疗效分析 被引量:13
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作者 杨春悦 张刚 +2 位作者 贾露莎 段庆同 李萍 《中国现代医学杂志》 CAS 北大核心 2021年第10期4-8,共5页
目的观察大剂量呋塞米持续静脉泵入对老年重度心力衰竭患者心功能的影响及疗效分析。方法选取2018年3月—2020年5月青岛阜外心血管病医院收治的重度心力衰竭患者50例。采用随机数字表法将患者分为治疗组与对照组,各25例。对照组给予常... 目的观察大剂量呋塞米持续静脉泵入对老年重度心力衰竭患者心功能的影响及疗效分析。方法选取2018年3月—2020年5月青岛阜外心血管病医院收治的重度心力衰竭患者50例。采用随机数字表法将患者分为治疗组与对照组,各25例。对照组给予常规药物治疗,治疗组在对照组基础上首次给予呋塞米40 mg/h微量泵入治疗,再以10 mg/h的速度持续静脉泵入200 mg呋塞米,观察两组患者治疗后临床疗效、症状改善时间、心功能指标及不良反应发生情况。结果治疗组临床总有效率高于对照组(P<0.05)。治疗组气促缓解时间、水肿消退时间短于对照组(P<0.05)。治疗组治疗前后左心室射血分数、心率、每搏心输出量及左心室舒张末期内径的差值大于对照组(P<0.05)。治疗组不良反应总发生率低于对照组(P<0.05)。结论大剂量呋塞米持续静脉泵入治疗重度心力衰竭疗效显著,可有效促进患者临床症状的改善,有利于提高心功能,降低药物不良反应,值得临床推广并应用。 展开更多
关键词 心力衰竭 呋塞米 老年人 心脏
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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
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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
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Evaluation of PCDD/Fs and metals emission from a circulating fluidized bed incinerator co-combusting sewage sludge with coal 被引量:6
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作者 gang zhang Jing Hai +4 位作者 Jiang Cheng Zhiqi Cai Mingzhong Ren Sukun zhang Jieru zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第1期231-235,共5页
The emission characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and heavy metals were evaluated during co-combustion of sewage sludge with coal from a circulating fluidized bed incinera... The emission characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and heavy metals were evaluated during co-combustion of sewage sludge with coal from a circulating fluidized bed incinerator. The stack gas, slag and fly ash samples were sampled and analyzed. The gas-cleaning system consisted of electrostatic precipitators and a semi-dry scrubber. Results showed that the stack gas and fly ash exhibited mean dioxin levels of 9.4 pg I-TEQ/Nm3 and 11.65 pg I-TEQ/g, respectively, and showed great similarities in congener profiles. By contrast, the slag presented a mean dioxin level of 0.15 pg I-TEQ/g and a remarkable difference in congener profiles compared with those of the stack gas and fly ash. Co-combusting sewage sludge with coal was able to reduce PCDD/Fs emissions significantly in comparison with sewage sludge mono-combustion. The leaching levels of Hg, Pb, Cd, Ni, Cr, Cu, and As in the fly ash and slag were much lower than the limits of the environmental protection standard in China. These suggest that the co-combustion of sewage sludge and coal is an advisable treatment method from an environmental perspective. 展开更多
关键词 CO-COMBUSTION PCDD/FS sewage sludge heavy metals
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Analysis of an improved acquisition method for high-dynamic BOC signal 被引量:7
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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)... 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. © 2016 Beijing Institute of Aerospace Information. 展开更多
关键词 Bins Mergers and acquisitions TITRATION
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