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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:5
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng heng chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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基于SEER数据库老年肺鳞癌患者的预后分析
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作者 衡晨 李娆 易静 《检验医学与临床》 CAS 2024年第8期1111-1117,共7页
目的基于SEER数据库分析影响老年肺鳞癌患者预后的危险因素,并构建预测模型。方法基于SEER数据库,选取2004—2015年确诊为肺鳞癌的25602例患者作为研究对象,按照7∶3随机分为训练集(17921例)与验证集(7681例);通过Kaplan-Meier生存曲线... 目的基于SEER数据库分析影响老年肺鳞癌患者预后的危险因素,并构建预测模型。方法基于SEER数据库,选取2004—2015年确诊为肺鳞癌的25602例患者作为研究对象,按照7∶3随机分为训练集(17921例)与验证集(7681例);通过Kaplan-Meier生存曲线分析肺鳞癌患者基本资料与预后的相关性;利用Cox回归和LASSO回归分析确定影响老年肺鳞癌患者预后的独立危险因素并构建列线图模型;以C-index、受试者工作特征(ROC)曲线、决策曲线评估列线图模型的预测性能。结果25602例患者中死亡17717例(69.2%);多因素Cox回归分析结果显示,年龄越大、高T分期、高N分期、高M分期、未接受手术是影响老年肺鳞癌患者预后不良的危险因素(P<0.05);训练集和验证集中用于评估列线图模型的C-index分别为0.732(95%CI:0.727~0.736)和0.733(95%CI:0.725~0.739),训练集列线图模型预测半年、1年、3年肺鳞癌患者预后的曲线的曲线下面积(AUC)分别为0.772(95%CI:0.764~0.779)、0.795(95%CI:0.789~0.802)、0.846(95%CI:0.839~0.852)。验证集列线图模型预测半年、1年、3年肺鳞癌患者预后的AUC分别为0.774(95%CI:0.763~0.785)、0.805(95%CI:0.795~0.815)、0.839(95%CI:0.829~0.850)。决策曲线结果显示,列线图模型的临床实用性良好。结论老年肺鳞癌患者年龄、T分期、N分期、M分期、手术情况对其预后有显著影响,构建的列线图模型能较为直观、准确地预测患者生存率,可为评估老年肺鳞癌患者预后提供科学依据。 展开更多
关键词 SEER数据库 列线图 肺鳞癌 生存预后 老年
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Anti-explosion performance and dynamic response of an innovative multi-layer composite explosion containment vessel
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作者 Zhen Wang heng chen +3 位作者 Qi Yuan Wenbin Gu Xingbo Xie Hongwei Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第6期105-121,共17页
An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional sing... An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel(SECV).Firstly,a series of experiments and finite element(FE)simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation results.Based on this,the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure,the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal explosions.Simulation results indicate that the end cover is the critical position for both the SECV and CECV.The maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the SECV.As a result,the explosive quantity the CECV can sustain is up to 20 times of that the SECV can sustain.Besides,as the explosive quantity increases,the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe,yielding plastic strain of the CECV in addition to elastic strain.The results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the CECV.For example,the CECV with fiber cloth layered in 0°/45°/90°/45°/0°mode has the optimal anti-capacity,compared to 0°/0°/0°/0°/0°and 0°/30°/60°/30°/0°modes.Overall,owing to remarkable anti-explosion capacity,this CECV can be regarded as a promising candidate for explosion resistance. 展开更多
关键词 Explosive container Honeycomb-fiber cloth ANTI-EXPLOSION Aluminum honeycomb core COMPOSITE
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Investigations of moiréartifacts induced by flux fluctuations in x-ray dark-field imaging
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作者 王志立 陈子涵 +2 位作者 顾瑶 陈恒 葛昕 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期621-628,共8页
X-ray dark-field imaging using a grating interferometer has shown potential benefits for a variety of applications in recent years.X-ray dark-field image is commonly retrieved by using discrete Fourier transform from ... X-ray dark-field imaging using a grating interferometer has shown potential benefits for a variety of applications in recent years.X-ray dark-field image is commonly retrieved by using discrete Fourier transform from the acquired phasestepping data.The retrieval process assumes a constant phase step size and a constant flux for each stepped grating position.However,stepping errors and flux fluctuations inevitably occur due to external vibrations and/or thermal drift during data acquisition.Previous studies have shown that those influences introduce errors in the acquired phase-stepping data,which cause obvious moiréartifacts in the retrieved refraction image.This work investigates moiréartifacts in x-ray dark-field imaging as a result of flux fluctuations.For the retrieved mean intensity,amplitude,visibility and dark-field images,the dependence of moiréartifacts on flux fluctuation factors is theoretically derived respectively by using a first-order Taylor series expansion.Results of synchrotron radiation experiments verify the validity of the derived analytical formulas.The spatial frequency characteristics of moiréartifacts are analyzed and compared to those induced by phase-stepping errors.It illustrates that moiréartifacts can be estimated by a weighted mean of flux fluctuation factors,with the weighting factors dependent on the moiréphase and different greatly for each retrieved image.Furthermore,moiréartifacts can even be affected by object’s features not displayed in the particular contrast.These results can be used to interpret images correctly,identify sources of moiréartifacts,and develop dedicated algorithms to remove moiréartifacts in the retrieved multi-contrast images. 展开更多
关键词 x-ray imaging dark-field imaging moiréartifacts flux fluctuations
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Analysis of refraction and scattering image artefacts in x-ray analyzer-based imaging
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作者 赵立明 王天祥 +5 位作者 马润康 顾瑶 罗梦丝 陈恒 王志立 葛昕 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期535-540,共6页
X-ray analyzer-based imaging(ABI) is a powerful phase-sensitive technique that can provide a wide dynamic range of density and extract useful physical properties of the sample. It derives contrast from x-ray absorptio... X-ray analyzer-based imaging(ABI) is a powerful phase-sensitive technique that can provide a wide dynamic range of density and extract useful physical properties of the sample. It derives contrast from x-ray absorption, refraction, and scattering properties of the investigated sample. However, x-ray ABI setups can be susceptible to external vibrations, and mechanical imprecisions of system components, e.g., the precision of motor, which are unavoidable in practical experiments. Those factors will provoke deviations of analyzer angular positions and hence errors in the acquired image data.Consequently, those errors will introduce artefacts in the retrieved refraction and scattering images. These artefacts are disadvantageous for further image interpretation and tomographic reconstruction. For this purpose, this work aims to analyze image artefacts resulting from deviations of analyzer angular positions. Analytical expressions of the refraction and scattering image artefacts are derived theoretically and validated by synchrotron radiation experiments. The results show that for the refraction image, the artefact is independent of the sample’s absorption and scattering signals. By contrast, artefact of the scattering image is dependent on both the sample’s refraction and scattering signals, but not on absorption signal.Furthermore, the effect of deviations of analyzer angular positions on the accuracy of the retrieved images is investigated,which can be of use for optimization of data acquisition. This work offers the possibility to develop advanced multi-contrast image retrieval algorithms that suppress artefacts in the retrieved refraction and scattering images in x-ray analyzer-based imaging. 展开更多
关键词 x-ray imaging analyzer-based imaging image artefacts
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气相反应对CVD生长石墨烯的影响 被引量:6
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作者 陈恒 张金灿 +1 位作者 刘晓婷 刘忠范 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第1期36-51,共16页
化学气相沉积法(CVD)制备的石墨烯薄膜具有质量高、均匀性好、层数可控且可放大等优点,近年来受到了学术界和工业界的广泛关注。在高温CVD生长过程中,除衬底表面的反应外,气相反应同样会影响石墨烯的生长行为和薄膜质量。本文将综述气... 化学气相沉积法(CVD)制备的石墨烯薄膜具有质量高、均匀性好、层数可控且可放大等优点,近年来受到了学术界和工业界的广泛关注。在高温CVD生长过程中,除衬底表面的反应外,气相反应同样会影响石墨烯的生长行为和薄膜质量。本文将综述气相反应对CVD生长石墨烯的影响:首先对CVD体系内的气相传质过程和气相反应进行了详细讨论;随后系统介绍了基于气相调控提高石墨烯的结晶性、洁净度、畴区尺寸、层数和生长速度的相关策略及其机理;最后对气相反应影响CVD生长石墨烯的规律进行总结,并展望了未来可能的发展方向。 展开更多
关键词 石墨烯薄膜 化学气相沉积 气相反应 高品质 可控制备
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超洁净石墨烯薄膜的制备方法 被引量:5
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作者 刘晓婷 张金灿 +1 位作者 陈恒 刘忠范 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第1期52-66,共15页
化学气相沉积(Chemical vapor deposition,CVD)法制备的石墨烯薄膜具有质量高、可控性好、可放大等优点,近年来受到了学术界和工业界的广泛关注。然而,近期研究结果表明,在高温CVD生长石墨烯的过程中,伴随着许多副反应,这些副反应会导... 化学气相沉积(Chemical vapor deposition,CVD)法制备的石墨烯薄膜具有质量高、可控性好、可放大等优点,近年来受到了学术界和工业界的广泛关注。然而,近期研究结果表明,在高温CVD生长石墨烯的过程中,伴随着许多副反应,这些副反应会导致石墨烯薄膜表面沉积大量的无定形碳污染物,造成石墨烯薄膜的"本征污染"现象。同时,这些污染物的存在会导致转移后的石墨烯薄膜表面更脏,对石墨烯材料和器件的性能带来严重影响。这也是CVD石墨烯薄膜的性能一直无法媲美机械剥离石墨烯的重要原因之一。事实上,超洁净生长方法制备得到的超洁净石墨烯薄膜在诸多指标上都给出了目前文献报道的最好结果,代表着石墨烯薄膜材料制备技术的发展前沿。本文首先对CVD法制备石墨烯过程中表面污染物的形成机理进行分析,然后综述了超洁净石墨烯薄膜的制备方法,并列举了超洁净石墨烯薄膜的优异性质。最后,总结并展望了超洁净石墨烯未来可能的发展方向和规模化制备面临的机遇与挑战。 展开更多
关键词 化学气相沉积 超洁净石墨烯 表面污染物成因 制备方法 优异性质
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Removal of carbonyl sulfide from CO_2 stream using AgNO_3-modified NaZSM-5 被引量:5
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作者 Yanjun Wang Shaoyun chen +2 位作者 heng chen Xingzhou Yuan Yongchun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第6期902-906,共5页
Removal of carbonyl sulfide(COS) from CO2 stream is significant for the production and utilization of food grade CO2. This study investigates the adsorption performance of Ag/NaZSM-5 as adsorbent prepared by incipient... Removal of carbonyl sulfide(COS) from CO2 stream is significant for the production and utilization of food grade CO2. This study investigates the adsorption performance of Ag/NaZSM-5 as adsorbent prepared by incipient wetness impregnation for the removal of COS from a CO2 stream in a fixed-bed adsorption apparatus. Effects of various conditions on the preparation of adsorbent, adsorption and desorption were intensively examined. The results revealed that COS can be removed to below 1×10-9from a CO2stream(1000 ppm COS/CO2) using Ag/NaZSM-5(10 wt% AgNO3) with an adsorption capacity of 12.86 mg·g-1. The adsorbent can be fully regenerated using hot air at 450 C. The adsorption ability remained stable even after eight cycles of regeneration. 展开更多
关键词 carbonyl sulfide adsorption π-complexation completely regeneration Ag-modified adsorbents
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Effective combined therapy for pulmonary epithelioid hemangioendothelioma: A case report 被引量:4
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作者 Xiu-Qin Zhang heng chen +3 位作者 Shu Song Yan Qin Li-Ming Cai Fang Zhang 《World Journal of Clinical Cases》 SCIE 2020年第10期2009-2015,共7页
BACKGROUND Pulmonary epithelioid hemangioendothelioma(P-EHE)is a rare disease.Thus far,consensus on a standard treatment for P-EHE has not been established given its low incidence worldwide.Apatinib combined with chem... BACKGROUND Pulmonary epithelioid hemangioendothelioma(P-EHE)is a rare disease.Thus far,consensus on a standard treatment for P-EHE has not been established given its low incidence worldwide.Apatinib combined with chemotherapy with doxorubicin/cyclophosphamide has been used as an effective combination treatment for human malignancies.However,the efficacy of this combination has not been reported in P-EHE cases.CASE SUMMARY We present the case of a 64-year-old woman with chest tightness,cough,and chest pain.Computed tomography showed multiple unresectable pulmonary nodules.She had been misdiagnosed with lung carcinoma and underwent gefitinib treatment at a hospital.Subsequently,the patient underwent a cardiothoracic surgery for further disease investigation.CD31,CD34,and Vimentin expression were detected in the resected nodule specimens by immunohistochemical analyses,and pathological analyses confirmed the diagnosis of P-EHE.Following this,four cycles of apatinib combined with chemotherapy with doxorubicin/cyclophosphamide were initiated.The patient demonstrated stabilization of multiple bilateral nodules and showed a dramatic improvement in the clinical presentation after combination treatment.The patient could not tolerate the side effects of chemotherapy.Therefore,she then continued apatinib monotherapy,which is ongoing to date.The patient was stable at the last follow-up after 24 mo.CONCLUSION Apatinib combined with chemotherapy with doxorubicin/cyclophosphamide may be an effective therapeutic option for P-EHE treatment. 展开更多
关键词 Pulmonary epithelioid hemangioendothelioma Apatinib DOXORUBICIN CYCLOPHOSPHAMIDE Combination therapy PROGNOSIS Case report
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Three Cases of COVID-19 Variant Delta With and Without Vaccination——Chengdu City,Sichuan Province,April-May,2021 被引量:5
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作者 heng chen Yi Mao +14 位作者 Zhenhua Duan Liang Wang Yue Cheng Yingxue Dai Haixia Luo Wenjun Xie Shuangfeng Fan Yuzhen Zhou Jingpei Xu Lan Feng Liwen Hu Zhu Liu Xian Liang Liangshuang Jiang Xiaoli Tuo 《China CDC weekly》 2021年第25期544-546,共3页
On April 26,2021,a 33-year-old male Chinese sailor returning from India via Kathmandu,Nepal,tested positive for the coronavirus disease 2019(COVID-19)by Chengdu Customs and was confirmed positive by Chengdu CDC(Case A... On April 26,2021,a 33-year-old male Chinese sailor returning from India via Kathmandu,Nepal,tested positive for the coronavirus disease 2019(COVID-19)by Chengdu Customs and was confirmed positive by Chengdu CDC(Case A).On May 2,2021,a housewife in the same flight tested positive for COVID-19 by Pengzhou CDC in Sichuan Province during her quarantine period and was confirmed positive by Chengdu CDC the next day(Case B). 展开更多
关键词 FIR Chengdu COV
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A Quantitative and Network Approach to Alignment Effects in L2 Continuation Tasks 被引量:2
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作者 heng chen 《Chinese Journal of Applied Linguistics》 2021年第3期399-416,432,共19页
The present study employed a quantitative and network approach to detect alignment effects in second language(L2) continuation tasks designed on the xu-argument(Wang, 2016). The materials used in this study were 6 sub... The present study employed a quantitative and network approach to detect alignment effects in second language(L2) continuation tasks designed on the xu-argument(Wang, 2016). The materials used in this study were 6 sub-corpora consisting of two selected input stories and two groups of L2 written production based on two continuation tasks. During continuation, the participants were required to continue in English a story with its ending removed, with one group reading and continuing the Chinese version and the other group the English version, and then switching their roles in the two tasks. Results show that the alignment effect differs across the two versions of continuation. Specifically, compared with the Chinese-version continuation, L2 learners produced more use of unigrams and bigrams similar to the input story in terms of lexical items, frequency and ranking correlations in the English-version task;on the other hand, the English-version continuation can facilitate generating linguistic networks that are much closer to the native English networks. Moreover, this research corroborates that written production in L2 continuation tasks can be influenced by input content. 展开更多
关键词 CONTINUATION alignment effect language network quantitative linguistics second language acquisition
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Quantitative coherence analysis of dual phase grating x-ray interferometry with source grating 被引量:1
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作者 Zhi-Li Wang Rui-Cheng Zhou +4 位作者 Li-Ming Zhao Kun Ren Wen Xu Bo Liu heng chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期595-600,共6页
Dual phase grating x-ray interferometry is compatible with common imaging detectors,and abandons the use of an absorption analyzer grating to reduce the radiation dose.When using x-ray tubes,an absorbing source gratin... Dual phase grating x-ray interferometry is compatible with common imaging detectors,and abandons the use of an absorption analyzer grating to reduce the radiation dose.When using x-ray tubes,an absorbing source grating must be introduced into the dual phase grating interferometer.In order to attain a high fringe visibility,in this work we conduct a quantitative coherence analysis of dual phase grating interferometry to find how the source grating affects the fringe visibility.Theoretical analysis shows that with the generalized Lau condition satisfied,the fringe visibility is influenced by the duty cycle of the source grating and the transmission through the grating bar.And the influence of the source grating profile on the fringe visibility is independent of the phase grating type.Numerical results illustrate that the maximum achievable fringe visibility decreases significantly with increasing transmission in the grating bar.Under a given transmission,one can always find an optimal duty cycle to maximize the fringe visibility.These results can be used as general guidelines for designing and optimizing dual phase grating x-ray interferometers for potential applications. 展开更多
关键词 x-ray imaging phase contrast grating interferometer fringe visibility
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Central neuromechanisms underlying control of intragastric pressure through acupuncture at Zusanli(ST36) in rats: the upper cervical cord is the key link between the ascending and descending pathways 被引量:3
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作者 Chun-yan Yong Shu chen +5 位作者 heng chen Xiao Chu Chao Zhang Cheng Tan Lan Ye Jiang-shan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第6期971-976,共6页
Sensory inputs stimulated by Zusanli(ST36) acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic parav... Sensory inputs stimulated by Zusanli(ST36) acupuncture in the abdomen are known to converge in the upper cervical cord. However, it is unclear whether these inputs are subsequently conveyed to the hypothalamic paraventricular nucleus and what kind of afferent fibers are involved. We focused on the upper cervical cord, where afferent inputs converge, and detected c-fos expression in oxytocinergic neurons. We found that Zusanli acupuncture therapy effectively elevated intragastric pressure, but inhibited expression of c-fos in oxytocinergic neurons of the paraventricular nucleus in upper cervical cord injured rats. These Zusanli acupuncture effects remained even after complete dorsal cord transection. However, after complete transection of the spinal cord or dorsolateral funiculus, the effects were significantly attenuated and even disappeared. These findings suggest that the paraventricular nucleus is responsible for pooling and integrating signals from the Zusanli acupuncture and sensory information from the intragastric pressure variation, thereby contributing to the regulation of intragastric pressure. The upper cervical cord serves as the key link between ascending and descending pathways, which conveys afferent inputs to the paraventricular nucleus through the dorsolateral funiculus. 展开更多
关键词 acupuncture descending ascending nucleus inhibited Acupuncture minutes sensory acupoint attenuated
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Demonstration of multi-Watt all-fiber superfluorescent source operating near 980 nm 被引量:1
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作者 Yankun Ren Jianqiu Cao +4 位作者 Hanyuan Ying heng chen Zhiyong Pan Shaojun Du Jinbao chen 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期216-219,共4页
The superfluorescent Yb-doped fiber source operating near 980 nm is studied. The design requirement is theoretically discussed aiming to suppress the amplified spontaneous emission around 1030 nm in the 980-rim superf... The superfluorescent Yb-doped fiber source operating near 980 nm is studied. The design requirement is theoretically discussed aiming to suppress the amplified spontaneous emission around 1030 nm in the 980-rim superfluorescent fiber source. Based on the theoretical study, a multi-Watt, all-fiber, bi-directional, pumped, superfluorescent source operating near 980 nm is designed and experimentally demonstrated for the first time, to the best of our knowledge. The recorded 8.38-W combined output power is obtained with a 3-dB bandwidth about 3.5 nm. The power scaling of the 980-nm superlfuorescent fiber source is limited by the parasitic laser oscillation. 展开更多
关键词 superfluorescence fiber source amplified spontaneous emission ytterbium-doped fiber
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含缬酪肽蛋白促进单链RNA和双链DNA病毒复制或释放机制的研究进展
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作者 徐娜 桓晨 郑柏松 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2020年第5期1099-1104,共6页
含缬酪肽蛋白(VCP)作为一种具有广泛功能的ATPase,在哺乳动物细胞内质网相关降解和泛素-蛋白酶体途径中发挥重要功能。VCP不仅参与真核细胞核酸的重建、膜损伤和细胞周期调控等生命活动,还在病毒对宿主细胞的感染、复制和释放过程中发... 含缬酪肽蛋白(VCP)作为一种具有广泛功能的ATPase,在哺乳动物细胞内质网相关降解和泛素-蛋白酶体途径中发挥重要功能。VCP不仅参与真核细胞核酸的重建、膜损伤和细胞周期调控等生命活动,还在病毒对宿主细胞的感染、复制和释放过程中发挥调控作用。VCP能够促进西尼罗河病毒(WNV)、丙型肝炎病毒(HCV)、脊髓灰质炎病毒(PV)、肠道病毒71型(EV71)、冠状病毒(CoV)、基孔肯雅病毒(CHIKV)、辛德毕斯病毒(SINV)和裂谷热病毒等单链RNA病毒的复制或释放,还能促进加州苜蓿多核核型多角体病毒(AcMNPV)和人类巨细胞病毒(HCMV)等双链DNA病毒的复制。VCP通过其ATPase酶活性及参与的内质网相关降解(ERAD)和泛素-蛋白酶体等途径促进单链RNA和双链DNA病毒的复制或释放。现从VCP促进多种单股正链RNA、双链DNA病毒的复制和病毒粒子释放等3个方面综述近年来VCP同病毒感染相关的研究进展,为抗病毒治疗提供新的思路。 展开更多
关键词 含缬酪肽蛋白 单链RNA病毒 双链DNA病毒 转录复制 生活周期
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Retrieval of multiple scattering contrast from x-ray analyzer-based imaging
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作者 heng chen Bo Liu +2 位作者 Li-Ming Zhao Kun Ren Zhi-Li Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期600-604,共5页
We present a moment-based alternative approach to retrieve multiple scattering contrasts from x-ray analyzer-based imaging. By use of the properties of moments of convolutions, the multiple-image radiography approach ... We present a moment-based alternative approach to retrieve multiple scattering contrasts from x-ray analyzer-based imaging. By use of the properties of moments of convolutions, the multiple-image radiography approach is theoretically validated. Furthermore, higher order moments of the object scattering distribution, inaccessible in multiple-image radiography, are simultaneously provided by this alternative approach. It is experimentally demonstrated that the skew and kurtosis information related to the distribution of sub-pixel features within the object can be obtained from those complementary contrasts. Finally, the sensitivity of the retrieved multiple scattering contrasts is investigated experimentally. The finding that the sensitivity is inversely proportional to the square root of the detected photon number essentially indicates that the retrieval of moments with an order higher than two can be achieved without increasing exposure time or dose. The presented alternative approach provides an access to the exploitation of multiple scattering contrasts, which is expected to be useful in biomedical research, materials science, security screening, etc. 展开更多
关键词 x-ray imaging analyzer-based imaging rocking curve moment analysis
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Biases of estimated signals in x-ray analyzer-based imaging
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作者 Jianlin Xia Wen Xu +4 位作者 Ruicheng Zhou Xiaomin Shi Kun Ren heng chen Zhili Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期571-576,共6页
Recently,a novel three-image algorithm has been proposed to retrieve the sample’s absorption,refraction,and scattering properties in x-ray analyzer-based imaging.The feasibility of the three-image algorithm was valid... Recently,a novel three-image algorithm has been proposed to retrieve the sample’s absorption,refraction,and scattering properties in x-ray analyzer-based imaging.The feasibility of the three-image algorithm was validated by synchrotron radiation experiments.However,it is unclear yet whether the estimated refraction and scattering signals are biased or not and how the analyzer angular position affects the biases in the estimated signals.For this purpose,the biases of the extracted refraction and scattering signals are theoretically derived for the three-image algorithm.The theoretical models are further confirmed by numerical experiments.The results show that both the estimated refraction and scattering signals are biased,and the biases are strongly dependent on the analyzer angular position.Besides,the biases also show dependence on the sample’s refraction and scattering properties locally.Those results can be used as general guidelines to optimize experimental parameters for bias reduction and accurate imaging of different features within the sample. 展开更多
关键词 x-ray imaging analyzer-based imaging three-image algorithm
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Clinicopathological and Immunohistochemical Features of Triple Negative Breast Cancer
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作者 heng chen Jinjun Li Wei Tan 《Advances in Breast Cancer Research》 2017年第4期93-99,共7页
Objective: To investigate the clinicopathological and immunohistochemical features of triple-negative breast cancer. Methods: The clinicopathological and immunohistochemical data (Ki-67, CK5/6, EGFR, E-Ca, SAM, P53, P... Objective: To investigate the clinicopathological and immunohistochemical features of triple-negative breast cancer. Methods: The clinicopathological and immunohistochemical data (Ki-67, CK5/6, EGFR, E-Ca, SAM, P53, P63, FAS) of 199 female patients who were treated for breast cancer in thyroid and breast surgery of Xiaogan Central Hospital from January 2015 to December 2016 was retrospectively analyzed by using spss22.0 statistical software and chi-square analysis. Results: Triple-negative breast cancer (replaced by TNBC below) and non-triple negative breast cancer (replaced by non TNBC below) in age, tumor size, lymph node metastasis, SAM, P53, P63 and FAS have no statistical difference (P > 0.05, see Table 1), while in WHO grade of invasive ductal carcinoma, KI-67, CK5/6, EGFR, E-Ca they have statistical differences (P 0.05, see Table 1). The invasive ductal carcinoma WHO grade of TNBC is higher than that of non TNBC. It’s positive rate of Ki-67, CK5/6, EGFR (96.67%, 58.33%, 72.22%) and negative rate of E-Ca (68.18%) are higher than those of non TNBC (75.74%, 29.03%, 18.92%, 30.38%) (P Table 1). Conclusions: The invasive ductal carcinoma WHO grade of TNBC is higher than that of non TNBC, while it’s Ki-67, CK5/6, EGFR positive rate and the negative rate of E-Ca are significantly higher than those of non TNBC. The immunohistochemical index above is expected to become potential targets for the treatment of TNBC. 展开更多
关键词 TNBC CLINICOPATHOLOGICAL FEATURES IMMUNOHISTOCHEMISTRY
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ⅢA-ⅡB multicomponent perovskite rare earth ferrites with promising electromagnetic wave absorption properties
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作者 Yanyan He Tao chen +8 位作者 Yanyu Pan Minzhong Huang Kaixian Wang Liyan Xue Yazhu Li Fengzhi Tan Fan Yang Tongkuan Xu heng chen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第6期1118-1127,I0005,共11页
Perovskite-type rare-earth ferrites(REFeO_(3))are promising materials for absorbing electromagnetic(EM)wave pollution.However,insufficient dielectric loss and poor impedance matching are key factors that limit the bro... Perovskite-type rare-earth ferrites(REFeO_(3))are promising materials for absorbing electromagnetic(EM)wave pollution.However,insufficient dielectric loss and poor impedance matching are key factors that limit the broader implementation of REFeO_(3).Herein,a series of multicomponent perovskite-type ferrites with strong EM wave absorption capabilities was prepared.Through the synergistic effect of chemical constitution regulation and entropy regulation,optimization of the dielectric loss and impedance matching is achieved by strengthening the structural defect mechanism,thus further adjusting the EM wave absorption performance.Compared with(LaGdSmNdBa)FeO_(3)(HE-1)and(LaGdPrSmNdBa)FeO_(3)(HE-2),(LaGdBa)FeO_(3)(ME-1)and(LaGdSmBa)FeO_(3)(ME-2)exhibit favorable performance,with optimal minimum reflection loss(RL_(min))of-56.35 dB(at 11.12 GHz)and-63.25 dB(at 7.22 GHz)and effective absorption bandwidth(EAB)of 4.46 and 4.72 GHz,respectively.This multicomponent design provides a new strategy for the development of EM wave absorption materials. 展开更多
关键词 Rare earths Multicomponent design Rare earth ferrites Entropy regulation Electromagnetic wave absorption
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Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer
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作者 Xuanyi Zhou heng chen +1 位作者 Yue Wu Tiange Zhang 《Building Simulation》 SCIE EI CSCD 2024年第6期907-932,共26页
To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological dat... To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat transfer.Firstly,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting tests.The relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then studied.Furthermore,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted separately.Finally,the equations in this paper are compared with the thermal coefficients in the main snow load codes.The results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow loads.In the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the buildings.Thermal coefficients are negatively correlated with indoor temperatures and roof heat transfer coefficients.When the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow load.The thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller. 展开更多
关键词 snowmelt model roof snow load building heat transfer thermal coefficient load code
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