期刊文献+
共找到1,519篇文章
< 1 2 76 >
每页显示 20 50 100
Homogenate extraction technology of camptothecine and hydroxycamptothecin from Camptotheca acuminata leaves 被引量:2
1
作者 史伟国 祖元刚 +1 位作者 赵春建 杨磊 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期168-170,I0004,共4页
Camptothecine (CPT) and hydroxycamptothecin (HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as th... Camptothecine (CPT) and hydroxycamptothecin (HCPT), two kinds of anti-cancer alkaloids, were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the ratio of material to liquid, ethanol concentration, and homogenate time. The optimum technology parameters for homogenate extraction of CPT and HCPT from C acuminata leaves were determined as homogenate time at 8 rain, ethanol concentration at 55% and the ratio of material to liquid at 1:15 (g:mL). By using the optimized parameters, we obtained 0.639‰ extraction rate for CPT and 0.437‰ for HCPT. The extraction yields of CPT and HCPT extracted by homogenating technology were higher than those by other extractive methods, such as ultrasonic, reflux, shaking in water bath. It is concluded that the homogenate extraction technology was an efficient method for extracting CPT and HCPT from C acuminata leaves, with characteristics of less extraction time and high yield. 展开更多
关键词 homogenate Camptotheca acuminata leaves camptothecine HYDROXYCAMPTOTHECIN
在线阅读 下载PDF
Epigallocatechin gallate content change of the fresh tea leaf homogenates extracted by different methods in extraction and preservation 被引量:4
2
作者 YANG Lei GAO Yan-hua ZU Yuan-gang LIU Xiao-na WANG Lei ZU Shu-chong 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期329-331,共3页
The fresh leaves of China green tea, Camellia sinensis, were collected from Fuyang, Zhejiang Province, China, in April. The tea polyphenols was extracted by four different methods (homogenized with distilled water at... The fresh leaves of China green tea, Camellia sinensis, were collected from Fuyang, Zhejiang Province, China, in April. The tea polyphenols was extracted by four different methods (homogenized with distilled water at room temperature, homogenized with 0.3% citric acid (w/v) at room temperature, 5- min boiling and homogenized with distilled water at room temperature, homogenized with 85℃ distilled water), and after preserving at room temperature, the change of the Epigallocatechin gallate (EGCG) contents of the extracts was investigated. Results indicated that the EGCG content of homogenate extracted with 85℃ distilled water was the highest before the extract was preserved, followed by that of the extract homogenized with 0.3% citric acid at room temperature. During preservation, EGCG content changed obviously. The EGCG contents of homogenates extracted with distilled water at room temperature and 85℃ distilled water declined quickly and separately reduced to 21.52% and 54.6% of their initial contents after preservation for 12 h. The EGCG contents extracted by 0.3% citric acid (w/v) solvent at room temperature and 5- min boiling/homogenized with distilled water at room temperature declined relatively slowly ,and separately reduced to 76.9% and 85.16% of their initial contents after preservation for 12 h. It was also found that the citric acid can prevent the degradation of EGCG and the extract solution color is light green 展开更多
关键词 Epigallocatechin gallate (EGCG) homogenate extraction Content change
在线阅读 下载PDF
Cryptococcal antigen testing of lung tissue homogenate improves pulmonary cryptococcosis diagnosis:Two case reports 被引量:1
3
作者 Wei-Yi Wang Yu-Lu Zheng Li-Bin Jiang 《World Journal of Clinical Cases》 SCIE 2022年第12期3893-3898,共6页
BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lav... BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lavage fluid),and cryptococcal antigen(CrAg)testing are helpful for a definitive diagnosis.However,these tests are sometimes falsely negative.PC is often misdiagnosed or underdiagnosed owing to the absence of obvert symptoms,poor imaging specificity,and false-negative laboratory tests.CASE SUMMARY We report two female patients who underwent computed tomography-guided percutaneous needle pulmonary biopsy of a lung nodule for a confirmed diagnosis.In both patients,the CrAg test on the lung biopsy tissue homogenate was positive,while the serum CrAg test was negative.Combined with the lung tissue pathology,we made the diagnosis of PC.Antifungal therapy was effective in both patients.CONCLUSION Given the findings of our cases and the literature review,lung tissue homogenate CrAg testing can be helpful in improving the diagnosis of PC. 展开更多
关键词 Lung tissue homogenate Cryptococcal antigen test Pulmonary cryptococcosis Lung biopsy DIAGNOSIS Case report
暂未订购
Maggot homogenate is associated with neural regeneration and wound healing in the rat
4
作者 Zhen Zhang Shouyu Wang +3 位作者 Xiliang Tian Zexu Zhao Jianing Zhang Decheng Lv 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第8期623-629,共7页
BACKGROUND:Live delivery limits the clinical application of maggot therapy. To date in China, there are no in vivo reports regarding wound healing mechanisms of maggot therapy or the effects of maggot homogenate on w... BACKGROUND:Live delivery limits the clinical application of maggot therapy. To date in China, there are no in vivo reports regarding wound healing mechanisms of maggot therapy or the effects of maggot homogenate on wound nerve regeneration.OBJECTIVE:To avoid complications due to the use of live maggots, an aseptic maggot homogenate was applied. Substance P (SP) and gene protein product 9.5 expression in a cutaneous wound was analyzed to explore possible mechanisms of neural regeneration and wound healing in the rat.DESIGN, TIME AND SETTING:A random grouping and controlled animal study was performed at the laboratory of the Department of Orthopedic Surgery, First Affiliated Hospital, Dalian Medical University from August 2008 to April 2009.MATERIALS:Live maggots were cultured and provided by the laboratory of the Department of Orthopedic Surgery of the First Affiliated Hospital, Dalian Medical University, China.METHODS:A total of 48 adult rats were selected and two acute, full-thickness wounds (round, 1.5 cm diameter) were created on the back of each rat. The two wounds were randomly assigned to homogenate product and control groups. Following two-step disinfection of maggots, a homogenate was produced from 10 maggots and applied to the wound area in the homogenate product group, while the wounds in the control group were treated with normal saline alone.MAIN OUTCOME MEASURES:On days 1,3, 7, 10, 14, and 21 following injury, the wound tissue was excised. Histological examination of the wound was observed by hematoxylin and eosin staining or Masson's Trichrome staining. SP and protein gene product 9.5 expressions were examined by immunohistochemistry to evaluate wound neural regeneration.RESULTS:On days 7, 10, and 14, the rate of wound healing was significantly greater in the homogenate product group compared with the control group (P 〈 0.05), and homogenate healing was better than that seen in the control group. On days 3, 7, and 10, SP expression in cells and regenerative nerves was significantly greater in the homogenate product group compared with the control group (P 〈 0.05). On days 7 and 10, protein gene product 9.5 expression was detected in the regenerative nerve, and expression level was significantly greater in the homogenate product group compared with the control group (P 〈 0.05).CONCLUSION:Maggot homogenate resulted in upregulated SP and protein gene product 9.5 expressions, thereby promoting neural regeneration and wound healing. 展开更多
关键词 maggot therapy wound healing NEUROPEPTIDES neural regeneration rats MAGGOTS maggot homogenate
暂未订购
Homogenate extraction technology of camptothecine and hydroxycamptothecin from Camptotheca acuminata leaves
5
作者 SHI Wei-guo ZU Yuan-gang +1 位作者 ZHAO Chun-jian YANG Lei 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期168-170,共3页
Camptothecine(CPT)and hydroxycamptothecin(HCPT),two kinds of anti-cancer alkaloids,were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the ratio o... Camptothecine(CPT)and hydroxycamptothecin(HCPT),two kinds of anti-cancer alkaloids,were extracted from Camptotheca acuminata leaves using homogenate extraction technology under different conditions such as the ratio of material to liquid,ethanol concentration,and homogenate time.The optimum technology parameters for homogenate extraction of CPT and HCPT from C.acuminata leaves were determined as homogenate time at 8 min,ethanol concentration at 55%and the ratio of material to liquid at 1:15(g:mL).By using the optimized parameters,we obtained 0.639‰extraction rate for CPT and 0.437‰for HCPT.The extraction yields of CPT and HCPT extracted by homogenating technology were higher than those by other extractive methods,such as ultrasonic,reflux,shaking in water bath.It is concluded that the homogenate extraction technology was an efficient method for extracting CPT and HCPT from C.acuminata leaves,with characteristics of less extraction time and high yield. 展开更多
关键词 homogenate Camptotheca acuminata leaves camptothecine HYDROXYCAMPTOTHECIN
在线阅读 下载PDF
Directional induction of dopaminergic neurons from neural stem cells using substantia nigra homogenates and basic fibroblast growth factor
6
作者 Jintao Li Qi Yan +2 位作者 Yiliu Ma Zhongtang Feng Tinghua Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第7期511-516,共6页
To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to invest... To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to investigate whether a homogenate of the substantia nigra of adult rats and/or basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons. Tyrosine hydroxylase-positive cells were observed exclusively after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor for 48 hours in vitro. However, in the groups treated with homogenate supernatant or basic fibroblast growth factor alone, tyrosine hydroxylase expression was not observed. Moreover, the content of dopamine in the culture medium of subventricular zone neurons was significantly increased at 48 hours after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor. Experimental findings indicate that the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons in the substantia nigra with the ability to secrete dopamine. 展开更多
关键词 directional induction in vitro homogenate of substantia nigra basic fibroblast growth factor subventricular zone neural stem cells dopaminergic neurons
在线阅读 下载PDF
The effect of natural plant-based homogenates as additives on the quality of yogurt:A review 被引量:6
7
作者 Xiankang Fan Xiefei Li +8 位作者 Lihui Du Jianhao Li Jue Xu Zihang Shi Chunwei Li Maoling Tu Xiaoqun Zeng Zhen Wu Daodong Pan 《Food Bioscience》 SCIE 2022年第5期85-98,共14页
Significant research has been conducted on using natural plant-based homogenates(NPBH)as additives to improve the quality of yogurt.This paper reviews the effects,mechanisms,and research methods of NPBH as additives t... Significant research has been conducted on using natural plant-based homogenates(NPBH)as additives to improve the quality of yogurt.This paper reviews the effects,mechanisms,and research methods of NPBH as additives to the probiotic content,texture,flavor,and nutritional value of yogurt.The mechanisms by which NPBH promotes the growth of lactic acid bacteria are reviewed,including nutrients in the homogenates,a suitable buffering environment,and the metabolic production of probiotics.Fructose,pectin,dietary fiber,protein,and polysaccharides are the primary influences on the yogurt texture.The aromatic precursors contained in NPBH,their contribution to yogurt flavor,and the health benefits of yogurt nutritional fortification are detailed.In the future,priority could be given to adding Chinese herbs(like wolfberry,saffron,and Rhodiola)with preventing alcoholic liver,anti-aging,blood pressure reduction,and other disease treatment or prevention functions to the yogurt to achieve a win-win situation.In addition,research on the function of NPBH yogurt should focus on the clinical implications. 展开更多
关键词 YOGURT Natural plant-based homogenates Food additives Gel strength FLAVOR
原文传递
A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study 被引量:1
8
作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
暂未订购
Influence of Homogenization on Microstructure Characteristics of Yttrium-Modified GH3535 Alloy
9
作者 Wang Yumiao Liang Wenjun +3 位作者 Li Xiaoli Jiang Sheng Zhou Xingtai Qiu Hanxun 《稀有金属材料与工程》 北大核心 2026年第2期322-332,共11页
The influence of homogenization parameters on element segregation,dendritic structure,and the precipitate evolution in the GH3535-0.08wt%Y alloy was investigated.Additionally,some specific homogenization parameters we... The influence of homogenization parameters on element segregation,dendritic structure,and the precipitate evolution in the GH3535-0.08wt%Y alloy was investigated.Additionally,some specific homogenization parameters were maintained constant throughout the experiments.Results indicate that the heat treatment at 1150℃for 10 h is the optimal homogenization condition.Following this optimal treatment,dendrite structures and element segregation are eliminated.Furthermore,both SiC and Y_(5)Si_(3)precipitates in the as-cast alloy decrease significantly.Conversely,the homogenization at 1188℃induces overheating defects within the alloy.Although SiC and Y_(5)Si_(3)phases also decrease,some large M6C phases can still be observed,adversely affecting subsequent forging processes. 展开更多
关键词 Ni-based alloy Y MICROSTRUCTURE HOMOGENIZATION CARBIDE
原文传递
Review and comparison of the methodology adopted for biodiesel production
10
作者 Milap G.Nayak 《Carbon Resources Conversion》 2026年第1期95-119,共25页
Biodiesel is a versatile energy source synthesized by trans esterifying various edible or nonedible oils using catalysts.It is preferable to diesel because of its higher flash points,reduced sulphur content,and biodeg... Biodiesel is a versatile energy source synthesized by trans esterifying various edible or nonedible oils using catalysts.It is preferable to diesel because of its higher flash points,reduced sulphur content,and biodegrad-ability.Biodiesel synthesis by esterification or transesterification methods involves conventional homogeneous or heterogeneous,enzymatic,supercritical,ultrasound,and microwave techniques.Since the operating condi-tions and mechanisms in each method differ,a comprehensive evaluation is necessary.This manuscript examines and covers a comprehensive summary of conventional heating,homogeneous and heterogeneous catalytic sys-tems.A review of enzymatic,supercritical,microwave,electrolysis,and ultrasound-assisted biodiesel synthesis techniques is also included.The comparative study of a microwave with a conventional system shows that it is superior to the latter due to inverse temperature gradient,high thermal efficiency,and reduction in activation energy,resulting in improved product purity and operating time.It performs better than slower enzymatic processes that involve product inhibition.It outperforms supercritical transesterification,which involves high operating conditions(temperature 200 to 300℃,pressure 20 to 30 MPa)and product deterioration.When compared to alternative approaches,microwave-aided transesterification significantly reduces response time and outperforms other methods.Techno-economic study and green chemistry principles are also favors in microwave-assisted biodiesel synthesis.Use of oleaginous microorganisms and microalgae as a feedstock,and process integration using valorization of waste glycerol,improved the sustainability of biodiesel synthesis. 展开更多
关键词 TRANSESTERIFICATION BIODIESEL Heterogeneous catalyst Homogeneous catalyst MICROWAVE ULTRASOUND
原文传递
Nucleation of Polymers in Nanopores and Nanocomposites with Nanoparticles/Nanosheets
11
作者 Ming Wang Ye Yao +4 位作者 Hui Zhao Wei-Long Ju Yun-Lan Su Du-Jin Wang Guo-Ming Liu 《Chinese Journal of Polymer Science》 2026年第1期1-12,I0007,共13页
Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the... Nucleation,which is the initial step of crystallization,critically governs the polymer crystallization behavior,influencing the crystallization temperature,kinetics,and morphology.However,the direct observation of the nucleation process in polymers remains elusive owing to spatial and temporal resolution limitations.This feature article summarizes the recent progress in understanding polymer nucleation within confined and interface-dominated environments,focusing on three representative systems:anodic aluminum oxide templates and nanocomposites containing nanoparticles or nanosheets.The interplay between finite size and interfacial effects has revealed some novel phenomena,such as homogeneous nucleation,surface nucleation,prefreezing,and supernucleation. 展开更多
关键词 Homogeneous nucleation Surface nucleation Prefreezing Supernucleation Confinement effects
原文传递
Urbanization alters the seasonality of bird communities across China
12
作者 Zhipeng Xie Haoting Duan +4 位作者 Baoming Zhang Minghui Zhou Ludan Zhang Jiehua Yu Jiekun He 《Avian Research》 2026年第1期1-9,共9页
Urbanization has profoundly reshaped biodiversity,yet its impacts on community seasonal changes remain poorly understood.Here,we used citizen science data from 839 bird species in 37 cities and their corresponding rur... Urbanization has profoundly reshaped biodiversity,yet its impacts on community seasonal changes remain poorly understood.Here,we used citizen science data from 839 bird species in 37 cities and their corresponding rural areas in China to assess how urbanization alters seasonal changes in bird communities.We calculated Sørensen beta dissimilarity indices(β_(sor))between seasons to compare the seasonality of communities in urban and rural areas and decomposed these indices into turnover(β_(sim))and nestedness(β_(nes))components.We evaluated whether there are differences in the latitudinal clines in community seasonality between urban and rural areas,and explored whether environmental and socio-economic factors affect the urbanization-driven changes in community seasonality.Our results show that the overall seasonalβ_(sor)in urban communities was 16.2%higher than in rural areas,due to a 49.5%increase inβ_(nes)(urban:0.22±0.12 vs.rural:0.15±0.08),but there was no significant difference inβ_(sim).In rural areas,β_(sor)increased with latitude,butβ_(sor)showed no latitudinal trend in urban communities.Human population emerges as a key predictor of urbanization-driven changes in the species turnover and nestedness components,with larger cities showing lower species turnover but higher nestedness components.We conclude that urbanization alters the seasonality of bird communities through nestedness components,decouples the relationship between community seasonality and latitude,and concentrates its impacts in densely populated cities.Future research must employ long-term monitoring to track how urbanization changes bird communities in space and time. 展开更多
关键词 Avian communities BIODIVERSITY Biotic homogenization Latitudinal gradients NESTEDNESS Seasonal beta diversity
在线阅读 下载PDF
Micropolar homogenization constitutive modeling and size effect analysis of lattice materials
13
作者 Tingrui CHEN Fan YANG +2 位作者 Jingchun ZHANG Dong HAN Qingcheng YANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期39-60,共22页
Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenizatio... Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenization methods based on the classical elasticity theory struggle to accurately describe the non-classical mechanical behaviors of lattice materials,especially when dealing with complex unit-cell geometries featured by non-symmetric configurations or non-single central node connections.In response to this limitation,this study establishes a generalized homogenization model based on the micropolar theory framework,employing Hill's boundary conditions to precisely predict the equivalent moduli of complex lattice materials.By introducing the independent rotational degree of freedom(DOF)characteristic of the micropolar theory,the proposed model successfully overcomes the limitation of conventional methods in accurately describing the asymmetric deformation and scale effects.We initially calculate the constitutive relations of two-dimensional(2D)cross-shaped multi-node chiral lattices and subsequently extend the method to three-dimensional(3D)lattices,successfully predicting the mechanical properties of both traditional and eccentric body-centered cubic(BCC)lattices.The theoretical model is validated through the finite element numerical verification which shows excellent consistency with the theoretical predictions.A further parametric study investigates the influence of geometric parameters,revealing the underlying size-effect mechanism.This paper provides a reliable theoretical tool for the design and property optimization of complex lattice materials. 展开更多
关键词 lattice material size effect micropolar theory homogenization method constitutive relationship
在线阅读 下载PDF
Niche vs.habitat:Insights of aging microplastics and wetland types on bacterial community assembly
14
作者 Yansong Shi Longrui Liang +1 位作者 Liang Meng Jingwen Hou 《Journal of Environmental Sciences》 2026年第1期221-232,共12页
Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community asse... Microorganisms can colonize the surface of microplastics(MPs)to form a distinctive microbiome,known as a“plastisphere”which is regarded as an anthropogenic niche for microbial growth.However,bacterial community assembly in virgin and aging MP plastispheres across different habitats is poorly understood.This study aims to assess the variations in bacterial community assembly across different niches and habitats with an in situ ex-periment,in which constructed forest wetland(FW),natural lake wetland(LW),and lotus pond wetland(LP)were habitats,and plastispheres of virgin and aging low-density polyethylene(LDPE)MPs,as well as surround-ing wetland soils were niches.Significant niche-related differences in bacterial communities were observed,with lower diversity and enrichment of potential plastic-degrading bacteria in the plastisphere than in the soil bacterial communities.Furthermore,habitat-related differences exerted a more pronounced influence on the beta-diversity patterns of the bacterial communities.The linear regression analyses indicated that the local species pool con-tributed more to bacterial community assembly in the LW wetland,whereas the relative abundance of species was the primary factor in the LP wetland.The null model analysis indicated that plastisphere bacterial communi-ties were predominantly driven by the stochastic process,with a more deterministic assembly observed in the LP wetland and soil bacterial communities.Additionally,the primary ecological process shaping plastisphere com-munities shifted from drift in the virgin LDPE to homogenising dispersal in the aging LDPE.This study provides new insights into the fate and ecological impacts of MPs in wetlands,thereby facilitating the effective regulations of plastic pollution. 展开更多
关键词 Plastisphere Community assembly mechanism Local species pool Stochastic assembly Homogeneous process
原文传递
Microscopic time-dependent mechanical behavior of shale derived from nanoindentation
15
作者 Cunbao Li Shilei Zhong +2 位作者 Heping Xie Changtai Zhou Jianjun Hu 《Deep Underground Science and Engineering》 2026年第1期160-175,共16页
Understanding the microscopic time-dependent mechanical behavior of shale is critical for assessing macroscopic creep and engineering applications.Grid nanoindentation experiments and nanoindentation creep tests were ... Understanding the microscopic time-dependent mechanical behavior of shale is critical for assessing macroscopic creep and engineering applications.Grid nanoindentation experiments and nanoindentation creep tests were systematically conducted to investigate microscopic creep behaviors in shale.The indentation creep displacements and creep rates of the shale's soft,intermediate,and hard phases showed the same evolution patterns.The creep deformation was much higher in the soft phase than in the other two phases.However,the difference in the steady-state creep rates between the three mechanical phases was negligible.A linear relationship was observed between the microscopic contact creep modulus and the microscopic Young's modulus,hardness,creep displacement,and creep rate.The primary mechanism of microscopic creep in shale revealed by the creep strain rate sensitivity parameter was the extension and closure of microcracks.The differences in the microscopic creep parameters derived from the experimental data using the deconvolution methods and representative point methods were evaluated,and the applicability of the two methods was described.The performances of commonly used creep models to predict the microscopic creep behaviors were evaluated.The Burgers model provided the best performance in predicting the steady-state creep deformation and creep rate.The ability of the Mori-Tanaka and Voigt-Reuss-Hill models to derive macroscopic parameters from microscopic mechanical parameters was compared.Both methods provided macroscopic Young's modulus values close to the experimental values;however,neither could predict macroscopic creep parameters based on microscopic creep parameters. 展开更多
关键词 creep models HOMOGENIZATION microscopic creep parameters nanoindentation creep
原文传递
MODELING OF A MICROPOLAR THIN FILM FLOW WITH RAPIDLY VARYING THICKNESS AND NON-STANDARD BOUNDARY CONDITIONS
16
作者 María ANGUIANO Francisco Javier SUÁREZ-GRAU 《Acta Mathematica Scientia》 2026年第1期209-242,共34页
In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary c... In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary conditions on the flat bottom.Assuming“Reynolds roughness regime”,in which the thickness of the domain is very small compared to the wavelength of the roughness(i.e.a very slight roughness),we rigorously derive a generalized Reynolds equation for pressure,clearly showing the roughness-induced effects.Moreover,we give expressions for the average velocity and microrotation. 展开更多
关键词 micropolar fluid thin-film flow rapidly oscillating boundary nonzero boundary conditions HOMOGENIZATION
在线阅读 下载PDF
REFINED BOHR INEQUALITIES AND A REFINED BOHR-ROGOSINSKI INEQUALITY ON COMPLEX BANACH SPACES
17
作者 Molla Basir AHAMED Sabir AHAMMED Hidetaka HAMADA 《Acta Mathematica Scientia》 2026年第1期19-38,共20页
In this paper,we first establish refined versions of the Bohr inequalities for the class of holomorphic functions from the unit ball BX of a complex Banach space X into ℂ.As applications,we will establish refined Bohr... In this paper,we first establish refined versions of the Bohr inequalities for the class of holomorphic functions from the unit ball BX of a complex Banach space X into ℂ.As applications,we will establish refined Bohr inequalities of functional type or of norm type for holomorphic mappings with lacunary series on the unit ball BX with values in higher dimensional spaces.Next,we obtain the Bohr-Rogosinski inequality for the class of holomorphic functions on BX.In addition,we establish an improved version of the Bohr inequality for holomorphic functions on BX.All the results are proved to be sharp. 展开更多
关键词 Banach spaces Bohr inequality Bohr-Rogosinski inequality homogeneous polynomial expansion Lacunary series
在线阅读 下载PDF
Two-Scale Concurrent Topology Optimization Method Based on Boundary Connection Layer Microstructure
18
作者 Hongyu Xu Xiaofeng Liu +5 位作者 Zhao Li Shuai Zhang Jintao Cui Zongshuai Zhou Longlong Chen Mengen Zhang 《Computers, Materials & Continua》 2026年第5期347-372,共26页
In two-scale topology optimization,enhancing the connectivity between adjacent microstructures is crucial for achieving the collaborative optimization of micro-scale performance and macro-scale manufacturability.This ... In two-scale topology optimization,enhancing the connectivity between adjacent microstructures is crucial for achieving the collaborative optimization of micro-scale performance and macro-scale manufacturability.This paper proposes a two-scale concurrent topology optimization strategy aimed at improving the interface connection strength.This method employs a parametric approach to explicitly divide the micro-design domain into a“boundary connection region”and a“free design domain”at the initial stage of optimization.The boundary connection region is used to generate a connection layer that enhances the interface strength,while the free design domain is not constrained by this layer,thus fully exploiting the design potential of the material layout.During the optimization process,the solid isotropic material with penalization(SIMP)method is first used to optimize the material distribution in the free design domain,and filtering and projection techniques are employed to alleviate numerical instability and obtain a clear topological structure.Subsequently,the effective performance of the microstructure is calculated through homogenization and transferred to the macro-scale for global response analysis.Throughout the iterative process,the geometry of the connection layer remains unchanged,and only the free design domain is optimized,thereby achieving a balance between high performance and good manufacturability.The effectiveness of the proposed method is verified through numerical examples. 展开更多
关键词 Two-scale topology optimization connectable microstructure interface connectivity boundary connection layer SIMP method homogenization theory
在线阅读 下载PDF
Fluorine-Decorated Metal-Organic Framework Separators Enable Ion-Screening Effects for Dendrite-Free Zinc Deposition
19
作者 Zhongliang Li Zuchen Hong +13 位作者 Chenxu Yuan Wenxi Ouyang Jinghua Liu Guiying Yang Sai Liu Yiling Fang Ke Lei Wenbin Wang Ying Li Hui Li Liang Tan Weihong Lu Yuepeng Cai Qifeng Zheng 《Energy & Environmental Materials》 2026年第1期64-73,共10页
Aqueous zinc-ion batteries(AZIBs)have emerged as a promising complement to lithium-ion batteries due to their inherent safety benefits.However,the cycle life of AZIBs is severely limited by the poor stability of zinc ... Aqueous zinc-ion batteries(AZIBs)have emerged as a promising complement to lithium-ion batteries due to their inherent safety benefits.However,the cycle life of AZIBs is severely limited by the poor stability of zinc anodes,manifested in uncontrolled dendritic growth and persistent side reactions,which hinder wider application.Herein,we report an ion-selective separator(UIO-66-4F/GF)achieved by in situ growth of a fluorine-functionalized metal-organic framework(UIO-66-4F)onto commercial glass fiber(GF).The synergistic mechanism,involving electrostatic repulsion between-F groups and SO_(4)^(2-)anions along with strong interactions between-F and Zn^(2+)cations,effectively restrict SO_(4)^(2-)migration,suppresses 2D Zn^(2+)diffusion across electrode interfaces,and enhances[Zn(H_(2)O)_(6)]^(2+)desolvation.Furthermore,the-F groups enable precise regulation of interfacial electric fields and Zn^(2+)concentration gradients,thereby homogenizing ion flux to realize dendrite-free Zn deposition.The UIO-66-4F separator achieves stable Zn||Zn cell operation for 1500 h at 1 mA cm^(-2)via oriented deposition and sustains long-term cycling over 1000 h at 1 mA cm^(-2),and delivers a Zn||Cu cell with 99.4%Coulombic efficiency.Moreover,the Zn|UIO-66-4F/GF|NH_(4)V_(4)O_(10) full cell represents an ultrastable cycling stability with a high capacity retention of 90%after 500 cycles at a current density of 1 A g^(-1). 展开更多
关键词 aqueous zinc-ion batteries dendrite-free fluorine-decorated homogenizing Zn^(2+)ion flux metal-organic framework
在线阅读 下载PDF
Studies on the biosynthesis of arteannuin——Ⅳ.The biosynthesis of arteanniuin and arteannuin B by the leaf homogenate of Artemisia annua L. 被引量:3
20
作者 WANG,Yu XIA,Zhi-Qiang ZHOU,Feng-Yi WU,Yu-Lin HUANG,Jing-Jian WANG,Zhi-Zhong Shanghai Institute of Organtic Chemistry,Chinese Academy of Siciences,Shanghai 200032 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1993年第5期457-463,共8页
Arteannuic acid and(-)11R,13-d(?)ydroarteannuic acid are the key intermediates in the biosynthesis of arteannuin by the leaf homogenate of Artemisia annua L.,and arteannuic acid and epoxyarteannuic acid are the interm... Arteannuic acid and(-)11R,13-d(?)ydroarteannuic acid are the key intermediates in the biosynthesis of arteannuin by the leaf homogenate of Artemisia annua L.,and arteannuic acid and epoxyarteannuic acid are the intermediates of arteannuin B.and epoxyarteannuic acid can not be transformed into arteannuin by the homogenate. 展开更多
关键词 The biosynthesis of arteanniuin and arteannuin B by the leaf homogenate of Artemisia annua L Studies on the biosynthesis of arteannuin
全文增补中
上一页 1 2 76 下一页 到第
使用帮助 返回顶部