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Adsorption–desorption behavior of atrazine on agricultural soils in China 被引量:17
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作者 Lin Yue ChengJun Ge +3 位作者 Dan Feng huamei Yu Hui Deng Bomin Fu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第7期180-189,共10页
Adsorption and desorption are important processes that affect atrazine transport,transformation,and bioavailability in soils.In this study,the adsorption–desorption characteristics of atrazine in three soils(laterit... Adsorption and desorption are important processes that affect atrazine transport,transformation,and bioavailability in soils.In this study,the adsorption–desorption characteristics of atrazine in three soils(laterite,paddy soil and alluvial soil) were evaluated using the batch equilibrium method.The results showed that the kinetics of atrazine in soils was completed in two steps:a"fast" adsorption and a "slow" adsorption and could be well described by pseudo-second-order model.In addition,the adsorption equilibrium isotherms were nonlinear and were well fitted by Freundlich and Langmuir models.It was found that the adsorption data on laterite,and paddy soil were better fitted by the Freundlich model;as for alluvial soil,the Langmuir model described it better.The maximum atrazine sorption capacities ranked as follows:paddy soil 〉 alluvial soil 〉 laterite.Results of thermodynamic calculations indicated that atrazine adsorption on three tested soils was spontaneous and endothermic.The desorption data showed that negative hysteresis occurred.Furthermore,lower solution pH value was conducive to the adsorption of atrazine in soils.The atrazine adsorption in these three tested soils was controlled by physical adsorption,including partition and surface adsorption.At lower equilibrium concentration,the atrazine adsorption process in soils was dominated by surface adsorption;while with the increase of equilibrium concentration,partition was predominant. 展开更多
关键词 Atrazine Adsorption Desorption Agricultural soils
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Hydration Mechanism of Sulphoaluminate Cement 被引量:15
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作者 何真 YANG huamei LIU Meiyan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第1期70-74,共5页
The feasibility of sulphoaluminate cement (SAC) utilization in support mortar was studied. Setting time and strength of as-received sulphoaluminate cement (SAC) paste were examined, hydration kinetics behavior was... The feasibility of sulphoaluminate cement (SAC) utilization in support mortar was studied. Setting time and strength of as-received sulphoaluminate cement (SAC) paste were examined, hydration kinetics behavior was determined through Isothermal Calorimeter, and hydration mechanism was investigated by X-Ray diffraction analysis (XRD) and field emission scanning electron microscopy analysis (FSEM). Results showed that as-received SAC contained 61% of anhydrous calcium sulfate (3CA'CaSO4) and dicalcium silicate (C2S). The strength after 1 day or 3 days grew to 68.6% or 85.7% of that after 28 days respectively, while most of hydration heat was released within 1 day. The emergency of three exothermic peaks at acceleration stage was found and hydration kinetics model was established choosing the terminal time of the first exothermic peak at accelerating stage as the beginning of accelerating stage. XRD analysis suggested that large amount of ettringite (AFt) was produced at early age and FSEM observation revealed that ettringite (AFt) formed in sulphoaluminate cement (SAC) paste was characterized of different morphology which was proved to be caused by different ion concentrations. 展开更多
关键词 sulphoaliminate cement ETTRINGITE hydration kinetics hydration mechanism
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Enhanced pyrocatalysis of the pyroelectric BiFeO_(3)/g-C_(3)N_(4) heterostructure for dye decomposition driven by cold–hot temperature alternation 被引量:11
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作者 Mingzi Chen Yanmin Jia +3 位作者 huamei Li Zheng Wu Tianyin Huang Hongfang Zhang 《Journal of Advanced Ceramics》 SCIE CAS CSCD 2021年第2期338-346,共9页
The BiFeO_(3)/g-C_(3)N_(4) heterostructure,which is fabricated via a simple mixing–calcining method,benefits the significant enhancement of the pyrocatalytic performance.With the growth of g-C_(3)N_(4) content in the... The BiFeO_(3)/g-C_(3)N_(4) heterostructure,which is fabricated via a simple mixing–calcining method,benefits the significant enhancement of the pyrocatalytic performance.With the growth of g-C_(3)N_(4) content in the heterostructure pyrocatalysts from 0 to 25%,the decomposition ratio of Rhodamine B(RhB)dye after 18 cold-hot temperature fluctuation(25-65℃)cycles increases at first and then decreases,reaching a maximum value of~94.2%at 10%while that of the pure BiFeO_(3) is~67.7%.The enhanced dye decomposition may be due to the generation of the internal electric field which strengthens the separation of the positive and negative carriers and further accelerates their migrations.The intermediate products in the pyrocatalytic reaction also have been detected and confirmed,which proves the key role of the pyroelectric effect in realizing the dye decomposition using BiFeO_(3)/g-C_(3)N_(4) heterostructure catalyst.The pyroelectric BiFeO_(3)/g-C_(3)N_(4) heterostructure shows the potential application in pyrocatalytically degrading dye wastewater. 展开更多
关键词 pyroelectric material BiFeO_(3) g-C_(3)N_(4) HETEROSTRUCTURE pyrocatalysis
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KAI1/CD82 gene expression in benign prostatic hyperplasia and late-stage prostate cancer in Chinese 被引量:6
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作者 Wei-LieHU Ying-QiuLI +4 位作者 Hui-XuHE Qing-RongLI YeTIAN Ri-QuanLAI huamei 《Asian Journal of Andrology》 SCIE CAS CSCD 2000年第3期221-224,共4页
Aim: To evaluate KAII/CD82 expression in Chinese patients with benign prostatic hyperplasia (BPH) and late-stage carcinoma of prostate (CaP). Methods: Thirty Chinese patients with benign prostatic hyperplasia and 34 w... Aim: To evaluate KAII/CD82 expression in Chinese patients with benign prostatic hyperplasia (BPH) and late-stage carcinoma of prostate (CaP). Methods: Thirty Chinese patients with benign prostatic hyperplasia and 34 withCaP (adenocarcinoma clinical stage C and D) were analyzed by means of immunohistochemical methods. Results:The KAII/CD82 expression in BPH tissue was all positive, which was uniformly located on the glandular cell mem-brane at the cell-to-cell borders, but KAII/CD82 expression in metastasis CaP tissues was either significantly lower thanthat of BPH or negative, and the immunostaining pattern was not continuous. In late-stage CAP KAII/CD82 expressionwas correlated inversely to the pathological grade ( P < 0.05), but not to clinical stage ( P > 0.05). Conclusion:The authors believe that decreased and negative KAII/CD82 expression in late-stage CaP may be related to tumor pro-gression and metastasis, and appears to be a prognostic marker. 展开更多
关键词 KAII/CD82 metastasis suppressor gene expression benign prostatic hyperplasia prostatic neoplasms IMMUNOHISTOCHEMISTRY
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Plasma-induced Mo-doped Co_(3)O_(4)with enriched oxygen vacancies for electrocatalytic oxygen evolution in water splitting 被引量:8
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作者 Yujie Huang Meng Li +4 位作者 Fei Pan Zhuoya Zhu huamei Sun Yawen Tang Gengtao Fu 《Carbon Energy》 SCIE CSCD 2023年第3期98-111,共14页
Heteroatomic substitution and vacancy engineering of spinel oxides can theoretically optimize the oxygen evolution reaction(OER)through charge redistribution and d-band center modification but still remain a great cha... Heteroatomic substitution and vacancy engineering of spinel oxides can theoretically optimize the oxygen evolution reaction(OER)through charge redistribution and d-band center modification but still remain a great challenge in both the preparation and catalytic mechanism.Herein,we proposed a novel and efficient Ar-plasma(P)-assisted strategy to construct heteroatom Mo-substituted and oxygen vacancies enriched hierarchical spinel Co_(3)O_(4)porous nanoneedle arrays in situ grown on carbon cloth(denoted P-Mo-Co_(3)O_(4)@CC)to improve the OER performance.Ar-plasma technology can efficiently generate vacancy sites at the surface of hydroxide,which induces the anchoring of Mo anion salts through electrostatic interaction,finally facilitating the substitution of Mo atoms and the formation of oxygen vacancies on the Co_(3)O_(4)surface.The P-Mo-Co_(3)O_(4)@CC affords a low overpotential of only 276 mV at 10 mA cm^(−2)for the OER,which is 58 mV superior to that of Mo-free Co_(3)O_(4)@CC and surpasses commercial RuO_(2)catalyst.The robust stability and satisfactory selectivity(nearly 100%Faradic efficiency)of P-Mo-Co_(3)O_(4)@CC for the OER are also demonstrated.Theoreti-cal studies demonstrate that Mo with variable valance states can efficiently regulates the atomic ratio of Co^(3+)/Co^(2+)and increases the number of oxygen vacancies,thereby inducing charge redistribution and tuning the d-band center of Co_(3)O_(4),which improve the adsorption energy of oxygen intermediates(e.g.,*OOH)on P-Mo-Co_(3)O_(4)@CC during OER.Furthermore,the two-electrode OER//HER electrolyzer equipped with P-Mo-Co_(3)O_(4)@CC as anode displays a low operation potential of 1.54 V to deliver a current density of 10 mA cm^(−2),and also exhibits good reversibility and anticurrent fluctuation ability under simulated real energy supply conditions,demonstrating the great potential of P-Mo-Co_(3)O_(4)@CC in water electrolysis. 展开更多
关键词 charge redistribution Mo‐Co_(3)O_(4) nanoneedle arrays oxygen evolution reaction oxygen vacancy water electrolysis
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基于MaxEnt滇牡丹潜在适生区研究 被引量:6
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作者 陈剑 原晓龙 +5 位作者 谭芮 华梅 杨卫 孙金金 呼延丽 王娟 《西部林业科学》 CAS 北大核心 2018年第3期24-29,共6页
滇牡丹是我国特有植物,天然分布区狭窄,野生资源正面临严重的人为破坏,对滇牡丹适生区进行研究,有助于滇牡丹的人工繁育、保护和利用。利用Max Ent模型,对全国19个气候因子和48个滇牡丹野生资源地理分布点进行分析,获得滇牡丹潜在适生... 滇牡丹是我国特有植物,天然分布区狭窄,野生资源正面临严重的人为破坏,对滇牡丹适生区进行研究,有助于滇牡丹的人工繁育、保护和利用。利用Max Ent模型,对全国19个气候因子和48个滇牡丹野生资源地理分布点进行分析,获得滇牡丹潜在适生区分布区范围,并进行可视化梯度分级。研究结果表明,全国范围内,滇牡丹潜在适生区仅分布于云南省、四川省、贵州省及西藏自治区,并主要集中分布于滇西北和滇中、滇东北的部分地区;19个气候因子中,温度季节性变化标准差、等温性、年均温变化范围这3个气候因子依次对滇牡丹天然分布起到最重要的作用,3个变量的值分别为4 100-4 900、46-49、22.50-26.00℃时,最适合滇牡丹的生长发育。研究结果可为滇牡丹种植选择优先区域提供科学参考。 展开更多
关键词 滇牡丹 Maxent模型 潜在适生区 气候因子
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Advancements in understanding mechanisms of hepatocellular carcinoma radiosensitivity:A comprehensive review 被引量:4
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作者 Gaoyuan Yang huamei Yan +8 位作者 Yongchang Tang Feng Yuan Mingbo Cao Yupeng Ren Yuxuan Li Zhiwei He Xiaorui Su Zhicheng Yao Meihai Deng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第3期266-282,共17页
Primary liver cancer is a significant health problem worldwide.Hepatocellular carcinoma(HCC)is the main pathological type of primary liver cancer,accounting for 75%-85%of cases.In recent years,radiotherapy has become ... Primary liver cancer is a significant health problem worldwide.Hepatocellular carcinoma(HCC)is the main pathological type of primary liver cancer,accounting for 75%-85%of cases.In recent years,radiotherapy has become an emerging treatment for HCC and is effective for various stages of HCC.However,radiosensitivity of liver cancer cells has a significant effect on the efficacy of radiotherapy and is regulated by various factors.How to increase radiosensitivity and improve the therapeutic effects of radiotherapy require further exploration.This review summarizes the recent research progress on the mechanisms affecting sensitivity to radiotherapy,including epigenetics,transportation and metabolism,regulated cell death pathways,the microenvironment,and redox status,as well as the effect of nanoparticles on the radiosensitivity of liver cancer.It is expected to provide more effective strategies and methods for clinical treatment of liver cancer by radiotherapy. 展开更多
关键词 Hepatocellular carcinoma RADIOSENSITIVITY EPIGENETICS non-coding RNA cell death METABOLISM tumor microenvironment reactive oxygen species NANOPARTICLE
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Recent progress on surface chemistryⅠ:Assembly and reaction 被引量:1
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作者 Xin Li Zhen Xu +62 位作者 Donglei Bu Jinming Cai huamei Chen Qi Chen Ting Chen Fang Cheng Lifeng Chi Wenjie Dong Zhenchao Dong Shixuan Du Qitang Fan Xing Fan Qiang Fu Song Gao Jing Guo Weijun Guo Yang He Shimin Hou Ying Jiang Huihui Kong Baojun Li Dengyuan Li Jie Li Qing Li Ruoning Li Shuying Li Yuxuan Lin Mengxi Liu Peinian Liu Yanyan Liu Jingtao Lü Chuanxu Ma Haoyang Pan JinLiang Pan Minghu Pan Xiaohui Qiu Ziyong Shen Shijing Tan Bing Wang Dong Wang Li Wang Lili Wang Tao Wang Xiang Wang Xingyue Wang Xueyan Wang Yansong Wang Yu Wang Kai Wu Wei Xu Na Xue Linghao Yan Fan Yang Zhiyong Yang Chi Zhang Xue Zhang Yang Zhang Yao Zhang Xiong Zhou Junfa Zhu Yajie Zhang Feixue Gao Yongfeng Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第12期43-94,共52页
Surface chemistry focuses on the investigation of the adsorption,migration,assembly,activation,reaction,and desorption of atoms and molecules at surfaces.Surface chemistry plays the pivotal roles in both fundamental s... Surface chemistry focuses on the investigation of the adsorption,migration,assembly,activation,reaction,and desorption of atoms and molecules at surfaces.Surface chemistry plays the pivotal roles in both fundamental science and applied technology.This review will summarize the recent progresses on surface assembly,synthesis and catalysis investigated mainly by scanning tunneling microscopy and atomic force microscopy.Surface assemblies of water and small biomolecules,construction of Sierpin′ski triangles and surface chirality are summarized.On-surface synthesis of conjugated carbo-and heterocycles and other kinds of carbon nanostructures are surveyed.Surface model catalysis,including single-atom catalysis and electrochemical catalysis,are discussed at the single-atom level. 展开更多
关键词 Surface chemistry ASSEMBLY Surface synthesis Catalysis on surface Surface electrochemical processes
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Effect of coral sand on the mechanical properties and hydration mechanism of magnesium potassium phosphate cement mortar
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作者 Hao LIU huamei YANG +3 位作者 Houzhen WEI Jining YU Qingshan MENG Rongtao YAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2024年第2期116-129,共14页
Damaged structures on coral islands have been spalling and cracking due to the dual corrosion of tides and waves.To ensure easy access to aggregate materials,magnesium potassium phosphate cement(MKPC)and coral sand(CS... Damaged structures on coral islands have been spalling and cracking due to the dual corrosion of tides and waves.To ensure easy access to aggregate materials,magnesium potassium phosphate cement(MKPC)and coral sand(CS)are mixed to repair damaged structures on coral islands.However,CS is significantly different from land-sourced sand in mineral composition,particle morphology,and strength.This has a substantial impact on the hydration characteristics and macroscopic properties of MKPC mortar.Therefore,in this study we investigated the compressive strength,interfacial mechanical properties,and corrosion resistance of MKPC CS mortar.Changes in the morphology,microstructure,and relative contents of hydration products were revealed by scanning electron microscope-energy dispersive spectrometer(SEM-EDS)and X-ray diffraction(XRD).The results indicated that the compressive strength increased linearly with the interfacial micro-hardness,and then stabilized after long-term immersion in pure water and Na2SO4 solution,showing excellent corrosion resistance.Compared with MKPC river sand(RS)mortar,the hydration products of CS mortar were an intermediate product 6KPO2·8H2O with a relative content of 3.9%at 1 h and 4.1%at 12 h.The hydration product MgKPO_(4)·6H_(2)O increased rapidly after 7-d curing,with an increased growth rate of 1100%.Our results showed that CS promoted the nucleation and formation of hydration products of MKPC,resulting in better crystallinity,tighter overlapping,and a denser interfacial transition zone.The results of this study provide technical support for applying MKPC mortar as a rapid repair material for damaged structures on coral islands. 展开更多
关键词 Magnesium potassium phosphate cement(MKPC) Coral sand(CS) Mechanical properties Corrosion resistance Hydration mechanism
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A clinical trial termination prediction model based on denoising autoencoder and deep survival regression
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作者 huamei Qi Wenhui Yang +1 位作者 Wenqin Zou Yuxuan Hu 《Quantitative Biology》 CAS CSCD 2024年第2期205-214,共10页
Effective clinical trials are necessary for understanding medical advances but early termination of trials can result in unnecessary waste of resources.Survival models can be used to predict survival probabilities in ... Effective clinical trials are necessary for understanding medical advances but early termination of trials can result in unnecessary waste of resources.Survival models can be used to predict survival probabilities in such trials.However,survival data from clinical trials are sparse,and DeepSurv cannot accurately capture their effective features,making the models weak in generalization and decreasing their prediction accuracy.In this paper,we propose a survival prediction model for clinical trial completion based on the combination of denoising autoencoder(DAE)and DeepSurv models.The DAE is used to obtain a robust representation of features by breaking the loop of raw features after autoencoder training,and then the robust features are provided to DeepSurv as input for training.The clinical trial dataset for training the model was obtained from the ClinicalTrials.gov dataset.A study of clinical trial completion in pregnant women was conducted in response to the fact that many current clinical trials exclude pregnant women.The experimental results showed that the denoising autoencoder and deep survival regression(DAE-DSR)model was able to extract meaningful and robust features for survival analysis;the C-index of the training and test datasets were 0.74 and 0.75 respectively.Compared with the Cox proportional hazards model and DeepSurv model,the survival analysis curves obtained by using DAE-DSR model had more prominent features,and the model was more robust and performed better in actual prediction. 展开更多
关键词 clinical trials denoising autoencoder DeepSurv experimental termination survival analysis
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Imaging polarity changes in pneumonia and lung cancer using a lipid droplet-targeted near-infrared fluorescent probe
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作者 huamei Zhang Jingjing Liu +5 位作者 Mingyue Li Shida Ma Xucong Zhou Aixia Meng Weina Han Jin Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第12期393-398,共6页
As the main organ of gas exchange,the lungs are susceptible to various exogenous attacks,and pneumonia is one of the major inflammatory diseases that threaten human health.Generally,pneumonia is a disease that occurs ... As the main organ of gas exchange,the lungs are susceptible to various exogenous attacks,and pneumonia is one of the major inflammatory diseases that threaten human health.Generally,pneumonia is a disease that occurs in the alveoli and respiratory bronchioles induced by pathogens and further causes local and systemic inflammatory responses.The development of pneumonia can bring various serious complications,including lung abscess,sepsis,meningitis,brain damage and hearing loss.Over the past few decades,the mortality rate of pneumonia patients has remained high.While lung cancer is another lung-related malignant tumors worldwide,with a low 5 year survival rate.Exploring the mechanisms of their occurrence and interaction between pneumonia and lung cancer is a challenging and meaningful task.The abnormalities of lipid droplets(LDs)polarity have been found strongly accompanied by many diseases,especially cancer,inflammation,and metabolic diseases.However,their exact role is not yet clear.Hence,it is significant to develop a novel detection method to observe the polarity changes of LDs,which would help to reveal the development process of diseases pneumonia and lung cancer.In this work,a new polarity-sensitive LDs-targeted near-infrared probe BFZ up to 712 nm was designed,according to the intramolecular charge transfer mechanism,which displayed high fluorescence intensity in low polarity while showing decreased fluorescence intensity in high-polarity conditions with a significant redshift.The BFZ was successfully applied to the change of LDs polarity in lipopolysaccharide(LPS)-stimulated A549 cells,and a mouse model of lung inflammation.It also tells the polarity differences between normal and tumor cells and between normal and tumor tissues.Moreover,the correlations between pneumonia and polarity changes were observed through the imaging experiments,which may provide an insightful method for the early diagnosis of pneumonia and lung cancer. 展开更多
关键词 Fluorescent probe Lipid droplets Polarity PNEUMONIA Lung cancer
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WOMEN PHOTOGRAPHERS PAY TRIBUTE TO ERA THROUGH LENSES
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作者 Zhang Lingli +15 位作者 Ying huamei Chen Jin Xu Lihua Dai Ruyu Liu Yanzhen Pan Meiyun Si Hangjun Xiao Mei Du Liping Chang Yu Huang Xiaoli Wang Juan Hou Ruifang Lu Xiaoting Zhang Xin Wan Guangying 《Women of China》 2024年第9期46-51,共6页
Members of the China Association of Women Photographers,from around the country,usedtheir cameras to record China's rapid development,beautiful scenery,traditional culture,and people's happylivesinthe new era.... Members of the China Association of Women Photographers,from around the country,usedtheir cameras to record China's rapid development,beautiful scenery,traditional culture,and people's happylivesinthe new era.In this edition,Women of China highlights some of those photographs,to share the beautiful moments with our readers. 展开更多
关键词 BEAUTIFUL culture LIVES
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Quick evaluation and regulation of the maximum instantaneous power and matching resistance for droplet-based electricity generators
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作者 Zhifeng Hu huamei Zhong +1 位作者 He Shan Ruzhu Wang 《Nano Research》 SCIE EI CSCD 2024年第11期9999-10007,共9页
Droplet-based electricity generators (DEGs) leveraging triboelectric effects are simple and high-performance devices for harvesting energy from ubiquitous water droplets. Instantaneous power plays a vital role in wide... Droplet-based electricity generators (DEGs) leveraging triboelectric effects are simple and high-performance devices for harvesting energy from ubiquitous water droplets. Instantaneous power plays a vital role in wide applications of DEGs. However, the governing law of the maximum instantaneous power and matching resistance is lacking and their determination suffers from heavy repetitive experiments, hindering the development of DEGs. Herein, we propose a quick evaluation method for the internal droplet impedance, instantaneous peak power, maximum instantaneous power and matching resistance which exhibits broad universality and excellent accuracy. Moreover, effects of diverse factors pertaining to droplets and devices are fully investigated, highlighting that the maximum instantaneous power and matching resistance can be effectively regulated across multiple orders of magnitudes by controlling the salt concentration. Our findings shed insights into the understanding, evaluation, and regulation of instantaneous power for DEGs, and shall promote the renovation of the DEG technology. 展开更多
关键词 droplet-based electricity generator maximum instantaneous power matching resistance quick evaluation method power regulation
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Genome-wide detection of additional fetal chromosomal abnormalities by cell-free DNA testing of 15,626 consecutive pregnant women 被引量:4
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作者 Hong Yao Ya Gao +13 位作者 Jia Zhao Rong Zhang Huixin Xu huamei Hu Yanmei Luo Yuying Yuan Meili Fu Hongyun Zhang Hui Jiang Wei Wang Huanming Yang Jian Wang Zhiqing Liang Fang Chen 《Science China(Life Sciences)》 SCIE CAS CSCD 2019年第2期215-224,共10页
Cell-free DNA(cfDNA) testing for common fetal trisomies(T21, T18, T13) is highly effective. However, the usefulness of cfDNA testing in detecting other chromosomal abnormalities is unclear. We evaluated the performanc... Cell-free DNA(cfDNA) testing for common fetal trisomies(T21, T18, T13) is highly effective. However, the usefulness of cfDNA testing in detecting other chromosomal abnormalities is unclear. We evaluated the performance of cfDNA testing for genome-wide abnormalities, and analyzed the incremental yield by reporting extra abnormalities. We performed genome-wide cfDNA testing in 15,626 consecutive pregnancies prospectively enrolled in this study. cfDNA testing results were reported and counseling was given depending on the presence of extra chromosomal abnormalities. cfDNA testing identified 190 cases(1.2%)of chromosomal abnormalities including 100 common trisomies and 90 additional abnormalities. By expanding the cfDNA reporting range to genome-wide abnormalities, the false positive rate increased to 0.39%(P<0.001) and positive predictive value(PPV) was reduced to 65.58%(P=0.42). However, the detection yield increased from 0.44% to 0.65%(P=0.014), and cfDNA testing detected 38.61%(39/101) additional abnormalities with no ultrasound and biochemical screening findings. cfDNA testing outperformed biochemical screening by showing 60 times higher true positive rate and fewer false negative results.Genome-wide cfDNA testing significantly increased the diagnostic yield by detecting extra abnormalities, especially those without diagnostic indications. Genome-wide cfDNA testing has fewer false positive and false negative results compared with biochemical screening. 展开更多
关键词 CELL-FREE DNA GENOME-WIDE CHROMOSOMAL ABNORMALITIES sensitivity SPECIFICITY PPV
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Quantitative effects of phase transition on solute partition coefficient,inclusion precipitation, and microsegregation for high-sulfur steel solidification 被引量:4
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作者 Lintao Gui Mujun Long +5 位作者 Shixin Wu Zhihua Dong Dengfu Chen Yunwei Huang huamei Duan Levente Vitos 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第10期2383-2395,共13页
Segregation and inclusion precipitation are the common behaviours of steel solidification, which are resulted from the redistribution and diffusion of the solute elements at the solid-liquid interface. The effect of t... Segregation and inclusion precipitation are the common behaviours of steel solidification, which are resulted from the redistribution and diffusion of the solute elements at the solid-liquid interface. The effect of the phase transition of high-sulfur free-cutting steel is quantified in the present work for the solute partition coefficient(ki), inclusion precipitation, and microsegregation by establishing a coupling model of microsegregation and inclusion precipitation, wherein the quantified dependencies of ki in terms of temperature, phase and carbon(C) content were applied. Results showed that the solidification temperature range and phase transition of high-sulfur steel that under different solidification paths and C contents were quite different, leading to differences in ki and eventually in microsegregation. kC,kP, and kS were mainly affected by phase composition and kSi was primarily by temperature, while kMn depended on both phase composition and temperature during solidification. Increasing the C content within the interval 0.07-0.48 wt%, the ‘proportion of the δ phase maintained temperature region during solidification’(Pδ), kave Pand kave S(kiave, the average value of the ki across the whole stages of solidification)decreased monotonically, whereas kave Cincreased linearly. The peritectic reaction impacted on the phase composition and ki, leading to the change in microsegregation. Such effect of the peritectic reaction was more significant at the last stage of solidification. When the Pδ was between 75% and 100%(corresponding to 0.07-0.16 wt% C), the solidification path resulted in a greater effect on the microsegregation of solutes C, P, and S because of the peritectic reaction. The microsegregation of solutes Mn and S were comprehensively influenced by kMn, kS and Mn S precipitation as well. The studies would help reveal the solute redistribution at the solid-liquid interface, and improve the segregation of high-sulfur steel by controlling the solidification and precipitation in practice. 展开更多
关键词 Phase transition MICROSEGREGATION SOLUTE PARTITION coefficient INCLUSION PRECIPITATION High-sulfur STEEL
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A review of cathode and electrolyte recovery from spent lithium-ion batteries: Recent technologies, processes and policies
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作者 Songming Zheng Tao Chen +4 位作者 Yujie Fang Chang He huamei Duan Shan Ren Chunbao Charles Xu 《Resources Chemicals and Materials》 2024年第3期188-229,共42页
Recently,lithium-ion batteries(LIBs),due to their superior performance,have been vastly applied in electronic,auto,and other industries,resulting in the generation of an increasing amount of spent LIBs.What’s worse,L... Recently,lithium-ion batteries(LIBs),due to their superior performance,have been vastly applied in electronic,auto,and other industries,resulting in the generation of an increasing amount of spent LIBs.What’s worse,LIBs contained potentially toxic substances,including heavy metals,toxic and flammable electrolyte containing LiBF_(4),LiClO_(4),and LiPF_(6).Conventional disposal of spent LIBs via landfill or incineration exerts tremendous pressure on the environment.It was necessary to adopt efficient,low-cost,and environmentally friendly approaches to valorizing spent LIBs,which could not only alleviate the shortage of rare resources by recycling valuable ele-ments such as Cu,Li,Mn,Ni,Co,and Al,but also eliminate the pollution of harmful components in batteries and realize the recycling and sustainable industry related to consumer electronics and electric vehicles(EVs).Given this,this paper summarized the recycling technologies of spent LIBs,including pyrometallurgy(melting reduction and roasting methods)and hydrometallurgy(leaching,precipitation,extraction,ion-exchange,elec-trochemical,sol-gel methods),and electrolyte recycling(organic solvent extraction and supercritical extraction methods).Pyrometallurgy technologies had relatively decent metal recovery rates but were associated with high energy consumption and atmospheric emission issues.Hydrometallurgical technologies were more environ-mentally friendly and efficient in recovering spent LIBs,although disposing of the wastewater generated from the process remained a challenge.In addition,the different industrial processes and various countries’related policies of recycling spent LIBs were investigated.In the end,the outlooks and future directions of recycling spent LIBs were proposed. 展开更多
关键词 Spent lithium-ion batteries RECOVERY Recycling technologies Materials POLICIES
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Magnetic properties of Jiaxian red clay sequences from northern Chinese Loess Plateau and its paleoclimatic significance 被引量:4
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作者 QIANG Xiaoke, AN Zhisheng, LI huamei, CHANG Hong & SONG Yougui 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 《Science China Earth Sciences》 SCIE EI CAS 2005年第8期1234-1245,共12页
Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the Chinese Loess Plateau as well as... Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the Chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern Chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern Chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern Chinese Loess Plateau, and it should be more arid in northern Chinese Loess Plateau. 展开更多
关键词 NORTHERN Chinese LOESS Plateau red clay MAGNETIC property PALEOCLIMATIC significance.
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Generation of low-cadmium rice germplasms via knockout of OsLCD using CRISPR/Cas9 被引量:2
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作者 huamei Chen Rong Ye +5 位作者 Ying Liang Shuchang Zhang Xiulian Liu Chongjun Sun Fangbai Li Jicai Yi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期138-152,共15页
The OsLCD gene,which has been implicated in cadmium (Cd) accumulation in rice,might be a useful target for CRISPR/Cas9 editing.However,the effects of Os LCD gene editing on Cd accumulation,plant growth,and yield trait... The OsLCD gene,which has been implicated in cadmium (Cd) accumulation in rice,might be a useful target for CRISPR/Cas9 editing.However,the effects of Os LCD gene editing on Cd accumulation,plant growth,and yield traits remain unknown.Here,we used CRISPR/Cas9to generate oslcd single mutants from indica and japonica rice cultivars.We also generated osnramp5 single mutants and oslcd osnramp5 double mutants in the indica background.When grown in Cd-contaminated paddy soils,all oslcd single mutants accumulated less Cd than the wild types (WTs).Consistent with this,oslcd single mutants grown in Cd-contaminated hydroponic culture accumulated significantly less Cd in the shoots as compared to WTs.This decrease in accumulation probably resulted from the reduction of Cd translocation under Cd stress.Oxidative damage also decreased,and plant growth increased in all oslcd single mutant seedlings as compared to WTs in the presence of Cd.Plant growth and most yield traits,as well essential element concentrations in rice seedling shoots,brown rice,and rice straw,were similar between oslcd single mutants and WTs.In the presence of Cd,Cd concentrations in the brown rice and shoots of oslcd osnramp5 double mutants were significantly decreased compared with WTs as well as osnramp single mutants.Our results suggested that OsL CD knockout may reduce Cd accumulation alone or in combination with other knockout mutations in a variety of rice genotypes;unlike Os Nramp5 mutations,Os LCD knockout did not reduce essential element contents.Therefore,Os LCD knockout might be used to generate low-Cd rice germplasms. 展开更多
关键词 CADMIUM RICE OsLCD Crispr/Cas9 editing
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Rock magnetic properties and palaeomagnetic results of sediments from a stone implement layer in the Bose Basin, Guangxi 被引量:3
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作者 YANG XiaoQiang ZHU ZhaoYu +3 位作者 ZHANG YiNan LI huamei ZHOU WenJuan YANG Jie 《Science China Earth Sciences》 SCIE EI CAS 2008年第3期441-450,共10页
Directional samples were taken to study rock magnetism and palaeomagnetic records from the Dongsheng profile, which is 5 m thick and on the northwest edge of the Bose Basin. Mineralogy and rock magnetism of typical sa... Directional samples were taken to study rock magnetism and palaeomagnetic records from the Dongsheng profile, which is 5 m thick and on the northwest edge of the Bose Basin. Mineralogy and rock magnetism of typical samples indicate that coarse granular titanomagnetite, and fine-grained hematite, superparamagnetic maghemite formed by pedogenesis are in the sediment, which has undergone many transformative processes during different stages of pedogenesis. Parallel samples were taken for thermal demagnetization (TH) (0 to 680°C) and alternating field (AF) demagnetization (0 to 80 mT) respectively. Experimental results of these two kinds of demagnetization illustrate that there are two or more magnetic components in the samples. Intensity of NRM decreases by almost 60% to 90% rapidly when the temperature ranges from 100°C to 350°C, with a steady magnetic component. It is impossible to analyze the magnetic components at high temperature because those fluctuate widely when the temperature is higher than 400°C. Steady magnetic components from 100°C to 350°C indicate that the remanence was mainly carried by fine-grained hematite formed by pedogenesis, reflecting a change in the geomagnetic field while the magnetite was being oxidized into hematite by chemical weathering after deposition. The formative age of the sediments cannot be obtained by magnetic methods in this profile. 展开更多
关键词 BOSE BASIN Dongsheng profile palaeomagnetic RECORDS
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HPLC测定丛生竹中总黄酮及(异)牡荆苷、(异)荭草苷的含量 被引量:3
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作者 华梅 陈剑 +5 位作者 毕玮 孔继君 呼延丽 李云琴 杨宇明 王娟 《西部林业科学》 CAS 北大核心 2018年第3期86-90,95,共6页
以勃氏甜龙竹竹叶为原料,对其中竹叶黄酮的超声提取工艺进行研究,同时采用高效液相色谱法(HPLC)对勃氏甜龙竹、箬竹、浦竹仔及椅子竹中总黄酮及牡荆苷、异牡荆苷、荭草苷、异荭草苷的含量进行测定。结果表明,勃氏甜龙竹超声提取最佳的... 以勃氏甜龙竹竹叶为原料,对其中竹叶黄酮的超声提取工艺进行研究,同时采用高效液相色谱法(HPLC)对勃氏甜龙竹、箬竹、浦竹仔及椅子竹中总黄酮及牡荆苷、异牡荆苷、荭草苷、异荭草苷的含量进行测定。结果表明,勃氏甜龙竹超声提取最佳的工艺为:甲醇作为提取溶剂、浓度为70%、料液比为1︰10(w︰v)、超声时间60min、温度40℃。在最佳提取条件下,勃氏甜龙竹中总黄酮得率能达到4.63%。采用高效液相色谱-外标法测定4种丛生竹中总黄酮,含量分别为0.795 2%、1.166 9%、0.092 6%、0.897 2%。勃氏甜龙竹、箬竹和椅子竹中均含有牡荆苷、异牡荆苷、荭草苷及异荭草苷,浦竹仔中仅含有牡荆苷和异牡荆苷。分析方法的建立,为丛生竹化学资源的利用奠定基础。 展开更多
关键词 丛生竹 勃氏甜龙竹 HPLC 竹叶黄酮 超声提取
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