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肺腺癌合并血管内大B细胞淋巴瘤1例并文献复习
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作者 王彤彤 陈小悦 +4 位作者 段国辰 张霄鹏 赵庆涛 许顺 赵焕芬 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第2期152-156,共5页
血管内大B细胞淋巴瘤(intravascular large B-cell lymphoma,IVLBCL)是一种侵袭性结外大B细胞淋巴瘤,在同一器官与其他恶性肿瘤同时发生非常罕见,尤其是肺。本文报道1例肺腺癌合并IVLBCL的罕见病例。患者因腹泻伴发热、咳嗽入院。胸部... 血管内大B细胞淋巴瘤(intravascular large B-cell lymphoma,IVLBCL)是一种侵袭性结外大B细胞淋巴瘤,在同一器官与其他恶性肿瘤同时发生非常罕见,尤其是肺。本文报道1例肺腺癌合并IVLBCL的罕见病例。患者因腹泻伴发热、咳嗽入院。胸部计算机断层扫描(computed tomography,CT)示右肺上叶不规则斑片状高密度影,边缘有磨玻璃影。入院后给予患者抗感染等治疗,但仍有间断低热(最高37.5 ℃)。经皮肺穿刺活检(percutaneous lung biopsy,PLB)病理诊断为贴壁生长为主的腺癌,局部考虑浸润。手术后病理诊断为肺浸润性非黏液性腺癌合并IVLBCL。本文通过分析其临床病理特征,并复习相关文献,以提高临床和病理医师对该肿瘤的认识,避免漏诊或误诊。 展开更多
关键词 肺肿瘤 肺腺癌 血管内大B细胞淋巴瘤
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Lung-Targeted Transgene Expression of Nanocomplexed Ad5 Enhances Immune Response in the Presence of Preexisting Immunity
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作者 Yilong Yang Shipo Wu +10 位作者 Yudong Wang Fangze Shao Peng Lv Ruihua Li Xiaofan Zhao Jun zhang xiaopeng zhang Jianmin Li Lihua Hou Junjie Xu Wei Chen 《Engineering》 SCIE EI CAS CSCD 2023年第8期127-139,共13页
Recombinant adenovirus serotype 5(Ad5)vector has been widely applied in vaccine development targeting infectious diseases,such as Ebola virus disease and coronavirus disease 2019(COVID-19).However,the high prevalence ... Recombinant adenovirus serotype 5(Ad5)vector has been widely applied in vaccine development targeting infectious diseases,such as Ebola virus disease and coronavirus disease 2019(COVID-19).However,the high prevalence of preexisting anti-vector immunity compromises the immunogenicity of Ad5-based vaccines.Thus,there is a substantial unmet need to minimize preexisting immunity while improving the insert-induced immunity of Ad5 vectors.Herein,we address this need by utilizing biocompatible nanoparticles to modulate Ad5–host interactions.We show that positively charged human serum albumin nanoparticles((+)HSAnp),which are capable of forming a complex with Ad5,significantly increase the transgene expression of Ad5 in both coxsackievirus–adenovirus receptor-positive and-negative cells.Furthermore,in charge-and dose-dependent manners,Ad5/(+)HSAnp complexes achieve robust(up to227-fold higher)and long-term(up to 60 days)transgene expression in the lungs of mice following intranasal instillation.Importantly,in the presence of preexisting anti-Ad5 immunity,complexed Ad5-based Ebola and COVID-19 vaccines significantly enhance antigen-specific humoral response and mucosal immunity.These findings suggest that viral aggregation and charge modification could be leveraged to engineer enhanced viral vectors for vaccines and gene therapies. 展开更多
关键词 Adenovirus serotype 5 VACCINE Preexisting immunity Nanoparticles Transgene expression
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纤维增强形状记忆聚合物复合材料的热变形行为 被引量:4
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作者 顾建平 孙慧玉 +1 位作者 张小朋 濮琦 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第10期59-65,共7页
通过将热力学内变量理论与Adam-Gibbs结构松弛模型相结合的方法,构建了适用于描述非晶态形状记忆聚合物(SMP)玻璃化转变过程中热变形行为的模型。在此基础上,利用复合材料细观力学分析方法进一步建立了纤维增强形状记忆聚合物复合材料(S... 通过将热力学内变量理论与Adam-Gibbs结构松弛模型相结合的方法,构建了适用于描述非晶态形状记忆聚合物(SMP)玻璃化转变过程中热变形行为的模型。在此基础上,利用复合材料细观力学分析方法进一步建立了纤维增强形状记忆聚合物复合材料(SMPC)热膨胀系数模型。模型中考虑了温度变化对基体弹性模量和泊松比在玻璃化转变过程中的影响。研究了一种含T300碳纤维增强相SMPC的热变形行为,结果表明,SMPC的各向热应变在升降温阶段几乎一致,仅在玻璃化转变附近微小分离;较快降温率导致的低温态热应变略小,而较快升温率导致平衡态温度更高; x向热应变随纤维倾角增大而增大,随纤维含量增大而减小。研究结果可对纤维增强SMPC的设计与应用提供一定理论参考。 展开更多
关键词 形状记忆聚合物复合材料 纤维 热变形 玻璃化转变 结构松弛
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Diffusion-tensor imaging as an adjunct to dynamic contrastenhanced MRI for improved accuracy of differential diagnosis between breast ductal carcinoma in situ and invasive breast carcinoma 被引量:13
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作者 Yuan Wang xiaopeng zhang +6 位作者 Kun Cao Yanling Li Xiaoting Li Liping Qi Lei Tang Zhilong Wang Shunyu Gao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第2期209-217,共9页
Objective: To determine the value of diffusion-tensor imaging (DTI) as an adjunct to dynamic contrastenhanced magnetic resonance imaging (DCE-MRI) for improved accuracy of differential diagnosis between breast du... Objective: To determine the value of diffusion-tensor imaging (DTI) as an adjunct to dynamic contrastenhanced magnetic resonance imaging (DCE-MRI) for improved accuracy of differential diagnosis between breast ductal carcinoma in situ (DCIS) and invasive breast carcinoma (IBC). Methods: The MRI data of 63 patients pathologically confirmed as breast cancer were analyzed. The conventional MRI analysis metrics included enhancement style, initial enhancement characteristic, maximum slope of increase, time to peak, time signal intensity curve (TIC) pattern, and signal intensity on FS- T2WI. The values of apparent diffusion coefficient (ADC), directionally-averaged mean diffusivity (D^vg), exponential attenuation (EA), fractional anisotropy (FA), volume ratio (VR) and relative anisotropy (RA) were calculated and compared between DCIS and IBC. Multivariate logistic regression was used to identify independent factors for distinguishing IBC and DCIS. The diagnostic performance of the diagnosis equation was evaluated using the receiver operating characteristic (ROC) curve. The diagnostic efficacies of DCE- MRI, DWI and DTI were compared independently or combined. Results: EA value, lesion enhancement style and TIC pattern were identified as independent factor for differential diagnosis of IBC and DCIS. The combination diagnosis showed higher diagnostic efficacy than a single use of DCE-MRI (P=0.02), and the area of the curve was improved from 0.84 (95% CI, 0.67-0.99) to 0.94 (95% CI, 0.85-1.00). Conclusions: Quantitative DTI measurement as an adjunct to DCE-MRI could improve the diagnostic performance of differential diagnosis between DCIS and IBC compared to a single use of DCE-MRI. 展开更多
关键词 Breast carcinoma in situ diffusion tensor imaging magnetic resonance imaging BREAST
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Review on structural control and modification of graphene oxide-based membranes in water treatment: From separation performance to robust operation 被引量:4
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作者 Ning zhang Wenxu Qi +5 位作者 Lili Huang En Jiang Junjiang Bao xiaopeng zhang Baigang An Gaohong He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第6期1348-1360,共13页
Membrane separation has become an important technology to deal with the global water crisis. The polymerbased membrane technology is currently in the forefront of water purification and desalination but is plagued wit... Membrane separation has become an important technology to deal with the global water crisis. The polymerbased membrane technology is currently in the forefront of water purification and desalination but is plagued with some bottlenecks. Laminated graphene oxide(GO) membranes exhibit excellent advantages in water purification and desalination due to the single atomic layer structure, hydrophilic property, rich oxygen-containing groups for modification, mechanical and chemical robust, anti-fouling properties, facile and large-scale production, etc. Thus the GO-based membrane technology is believed to offer huge opportunities for efficient and practical water treatment. This review systematically summarizes the current progress on the water flux and selectivity intensification, stability improvement, anti-fouling and anti-biofouling ability enhancement by structural control and modification. To improve the performance of the laminated GO membrane, interlayer spacing tunability and surface modification are mainly used to enhance its water flux and selectivity. It is found that the stability and biofouling also block the service life of the GO membrane. The crosslinking method is found to effectively solve the stability of GO membrane in aqueous environment. Introducing nanoparticles is a widely used method to improve the membrane biofouling ability. Overall, we believe that this review could provide benefit to researchers in the area of GO-based membrane technology for water treatment. 展开更多
关键词 Membranes Graphene OXIDE Water FLUX SELECTIVITY Stability FOULING
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无金属有机光催化原子转移自由基聚合的研究现状
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作者 李邦森 石建军 +2 位作者 孙天一 张小朋 史载锋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第6期182-190,共9页
自无金属光催化原子转移自由基聚合诞生以来,由于其绿色环保的优点受到众多学者的青睐。无金属光催化剂能够精确控制原子转移自由基聚合过程中聚合物的相对分子质量及分子量分布,优异的链端保真度有助于合成结构明确的嵌段聚合物。文中... 自无金属光催化原子转移自由基聚合诞生以来,由于其绿色环保的优点受到众多学者的青睐。无金属光催化剂能够精确控制原子转移自由基聚合过程中聚合物的相对分子质量及分子量分布,优异的链端保真度有助于合成结构明确的嵌段聚合物。文中综述了无金属有机光催化原子转移自由基聚合的外部驱动力对聚合反应的影响,介绍了有机光催化剂的设计开发,适用单体范围,引发剂和溶剂的选择对反应的引发效率、聚合单体的转化率、聚合物的相对分子质量及分子量分布的影响。此外,介绍了该聚合方法同其他聚合方法和学科的相互结合使用开发结构多样、功能优异材料的应用和未来研究的发展方向。 展开更多
关键词 原子转移自由基聚合 无金属有机光催化剂 合成 可控 机理 应用
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Repair of a small and crooked vesicovaginal fistula using electrocauterization 被引量:1
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作者 Weiyu zhang Kexin Xu +2 位作者 xiaopeng zhang Hao Hu Qi Wang 《Asian Journal of Urology》 2018年第3期182-183,共2页
Dear Editor,Vesicovaginal fistula(VVF)is an abnormal opening between the urinary bladder and the vagina.The condition has an immense psychological effect on patients due to the continuous leakage of urine or watery va... Dear Editor,Vesicovaginal fistula(VVF)is an abnormal opening between the urinary bladder and the vagina.The condition has an immense psychological effect on patients due to the continuous leakage of urine or watery vaginal discharge.The wet feeling and foul smell associated with leakage of urine cause social outcasting of the patients.This leads to immense emotional trauma and makes life miserable for the patient.The most common etiology for VVF in developing countries is obstructed labour[1],and in developed countries,it is abdominal hysterectomy[2].VVF poses a challenging problem to the surgeon.The location and the size of the fistula determine the extent of the patients’symptoms. 展开更多
关键词 FISTULA VAGINAL URINE
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Level of detail technique for plant models 被引量:2
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作者 xiaopeng zhang Qingqiong DENG~ Marc JAEGER 《中国体视学与图像分析》 2006年第4期235-242,共8页
Realistic modelling and interactive rendering of forestry and landscape is a challenge in computer graphics and virtual reality.Recent new developments in plant growth modelling and simulation lead to plant models fai... Realistic modelling and interactive rendering of forestry and landscape is a challenge in computer graphics and virtual reality.Recent new developments in plant growth modelling and simulation lead to plant models faithful to botanical structure and development,not only representing the complex architecture of a real plant but also its functioning in interaction with its environment.Complex geometry and material of a large group of plants is a big burden even for high performances computers,and they often overwhelm the numerical calculation power and graphic rendering power.Thus,in order to accelerate the rendering speed of a group of plants,software techniques are often developed.In this paper,we focus on plant organs,i.e.leaves,flowers,fruits and inter-nodes.Our approach is a simplification process of all sparse organs at the same time,i.e.,Level of Detail(LOD),and multi-resolution models for plants.We do explain here the principle and construction of plant simplification.They are used to construct LOD and multi-resolution models of sparse organs and branches of big trees.These approaches take benefit from basic knowledge of plant architecture,clustering tree organs according to biological structures.We illustrate the potential of our approach on several big virtual plants for geometrical compression or LOD model definition.Finally we prove the efficiency of the proposed LOD models for realistic rendering with a virtual scene composed by 184 mature trees. 展开更多
关键词 计算机图形学 虚拟现实 仿真模型 细节技术 植物模型
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Co_(3)O_(4) with ordered pore structure derived from wood vessels for efficient Hg^(0) oxidation
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作者 xiaopeng zhang Cheng Gao +7 位作者 Ziwei Wang Ximiao Wang Jie Cheng Xinxin Song Xiangkai Han Ning zhang Junjiang Bao Gaohong He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期215-221,共7页
Catalytic oxidation of Hgo to Hg~O is an efficient way to remove Hg^(0) from coal-fired flue gas.The catalyst with ordered pore structure can lower mass transfer resistance resulting in higher Hg^(0) oxidation efficie... Catalytic oxidation of Hgo to Hg~O is an efficient way to remove Hg^(0) from coal-fired flue gas.The catalyst with ordered pore structure can lower mass transfer resistance resulting in higher Hg^(0) oxidation efficiency.Therefore,in the present work,wood vessels were used as sacrificial template to obtain Co_(3)O_(4) with ordered pore structure.SEM and BET results show that,when the mass concentrations of Co(NO_(3))_(2)·6H_(2)O was 20%,the obtained catalyst(Co_(3)O_(4) [20%Co(NO_(3))_(2)])possesses better pore structure and higher surface area.It will expose more available surface active sites and lower the mass transfer resistance.Furthermore,XPS results prove that Co_(3)O_(4) [20%Co(NO_(3))_(2)]has the highest ratio of chemisorbed oxygen which plays an important role in Hg^(0) oxidation process.These results lead to a better Hg^(0) oxidation efficiency of Co_(3)O_(4) [20%Co(NO_(3))_(2)],which is about 90%in the temperature range of 200 to 350℃,Furthermore,Co_(3)O_(4) [20%Co(NO_(3))_(2)]has a stable catalytic activity,and its Hg^(0) oxidation efficiency maintains above 90%at 250℃even after 90 h test,A probable reaction mechanism is deduced by the XPS results of the fresh,used and regenerated catalyst of Co_(3)O_(4) [20%Co(NO3)2].Chemisorbed oxygen can react with Hg^(0) forming HgO with the reduction of Co^(3+)to Co^(2)+.And lattice oxygen and gaseous oxygen can supplement the consumption of chemisorbed oxygen to oxidize Co^(2+)to Co^(3+). 展开更多
关键词 Wood vessel Elemental mercury Co_(3)O_(4) Ordered porestructure
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Bone metastasis is a late-onset and unfavorable event in survivors of gastric cancer after radical gastrectomy:Results from a clinical observational cohort
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作者 Cheng zhang xiaopeng zhang +7 位作者 Chong Feng Yahui Yang Minmin Xie Ying Feng Zhijun Wu Hui Xu Changhao Wu Tai Ma 《Cancer Pathogenesis and Therapy》 2024年第1期50-57,共8页
Background The timing and incidence of recurrent bone metastasis(BM)after radical gastrectomy in patients with gastric cancer(GC)as well as the survival of these patients were not fully understood.The aim of this stud... Background The timing and incidence of recurrent bone metastasis(BM)after radical gastrectomy in patients with gastric cancer(GC)as well as the survival of these patients were not fully understood.The aim of this study was to analyze the data of an observational GC cohort and identify patients who underwent curative gastrectomy and had recurrent BM to describe and clarify the pattern and profile of BM evolution after surgery.Methods Data were retrieved from a hospital-based GC cohort,and patients who underwent upfront radical gastrectomy were selected.The time points of specific organ metastatic events were recorded,and the person-year incidence rate of metastatic events was calculated.The latency period of BM events after gastrectomy was measured and compared with that of the other two most common metastatic events,liver metastasis(LM)and distant lymph node metastasis(LNM),using analysis of variance.Propensity score matching and subgroup analysis were used for sensitivity analysis.Results A total of 1324 GC cases underwent radical gastrectomy between January 2011 and December 2021.Of these,67 BM,218 LM,and 248 LNM occurred before the last follow-up.The incidence of BM events was 1.7/100 person-years,which was approximately 3-fold lower than that of LM and distant LNM events(5.5 and 6.3 per 100 person-years,respectively).BM events had a significantly longer latency(median time,16.5 months)than LM and LNM events(11.1 and 12.0 months,respectively).Recurrent BM led to a worse prognosis(median survival,4.5 months)than those of LM and LNM events(median survival,7.7 and 7.1 months,respectively).However,no difference in overall survival after gastrectomy was observed among the groups.Conclusions Compared with other common metastatic events,BM in GC after gastrectomy is a late-onset event indicating poor survival. 展开更多
关键词 Stomach neoplasms Neoplasm metastasis INCIDENCE Survival analysis Propensity score
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Diel dynamics of multi-omics in elkhorn fern provide new insights into weak CAM photosynthesis 被引量:1
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作者 Cheng Li Wenjie Huang +15 位作者 Xiaoxu Han Guohua Zhao Wenyang zhang Weijun He Bao Nie Xufeng Chen Taijie zhang Wenhui Bai xiaopeng zhang Jingjing He Cheng Zhao Alisdair RFernie Timothy JTschaplinski Xiaohan Yang Shijuan Yan Li Wang 《Plant Communications》 SCIE CSCD 2023年第5期208-222,共15页
Crassulacean acid metabolism(CAM)has high water-use efficiency(WUE)and is widely recognized to have evolved from C3 photosynthesis.Different plant lineages have convergently evolved CAM,but the molecular mechanism tha... Crassulacean acid metabolism(CAM)has high water-use efficiency(WUE)and is widely recognized to have evolved from C3 photosynthesis.Different plant lineages have convergently evolved CAM,but the molecular mechanism that underlies C3-to-CAM evolution remains to be clarified.Platycerium bifurcatum(elkhorn fern)provides an opportunity to study the molecular changes underlying the transition from C3 to CAM photosynthesis because both modes of photosynthesis occur in this species,with sporotrophophyll leaves(SLs)and cover leaves(CLs)performing C3 and weak CAM photosynthesis,respectively.Here,we report that the physiological and biochemical attributes of CAM in weak CAM-performing CLs differed from those in strong CAM species.We investigated the diel dynamics of the metabolome,proteome,and transcriptome in these dimorphic leaves within the same genetic background and under identical environmental conditions.We found that multi-omic diel dynamics in P.bifurcatum exhibit both tissue and diel effects.Our analysis revealed temporal rewiring of biochemistry relevant to the energy-producing pathway(TCA cycle),CAM pathway,and stomatal movement in CLs compared with SLs.We also confirmed that PHOSPHOENOLPYRUVATE CARBOXYLASE KINASE(PPCK)exhibits convergence in gene expression among highly divergent CAM lineages.Gene regulatory network analysis identified candidate transcription factors regulating the CAM pathway and stomatal movement.Taken together,our results provide new insights into weak CAM photosynthesis and new avenues for CAM bioengineering. 展开更多
关键词 Platycerium bifurcatum crassulacean acid metabolism multi-omics transcription factor PPCK convergent evolution
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Achieving desired nodal lines in freely vibrating structures via material-field series-expansion topology optimization
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作者 Yi YAN xiaopeng zhang +2 位作者 Jiaqi HE Dazhi WANG Yangjun LUO 《Frontiers of Mechanical Engineering》 SCIE CSCD 2023年第3期187-201,共15页
Accurately controlling the nodal lines of vibrating structures with topology optimization is a highly challenging task.The major difficulties in this type of problem include a large number of design variables,the high... Accurately controlling the nodal lines of vibrating structures with topology optimization is a highly challenging task.The major difficulties in this type of problem include a large number of design variables,the highly nonlinear and multi-peak characteristics of iteration,and the changeable orders of eigenmodes.In this study,an effective material-field series-expansion(MFSE)-based topology optimization design strategy for precisely controlling nodal lines is proposed.Here,two typical optimization targets are established:(1)minimizing the difference between structural nodal lines and their desired positions,and(2)keeping the position of nodal lines within the specified range while optimizing certain dynamic performance.To solve this complex optimization problem,the structural topology of structures is first represented by a few design variables on the basis of the MFSE model.Then,the problems are effectively solved using a sequence Kriging-based optimization algorithm without requiring design sensitivity analysis.The proposed design strategy inherently circumvents various numerical difficulties and can effectively obtain the desired vibration modes and nodal lines.Numerical examples are provided to validate the proposed topology optimization models and the corresponding solution strategy. 展开更多
关键词 nodal line topology optimization structural dynamics design material-field series-expansion
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Joint specular highlight detection and removal in single images via Unet-Transformer
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作者 Zhongqi Wu Jianwei Guo +3 位作者 Chuanqing Zhuang Jun Xiao Dong-Ming Yan xiaopeng zhang 《Computational Visual Media》 SCIE EI CSCD 2023年第1期141-154,共14页
Specular highlight detection and removal is a fundamental problem in computer vision and image processing.In this paper,we present an efficient endto-end deep learning model for automatically detecting and removing sp... Specular highlight detection and removal is a fundamental problem in computer vision and image processing.In this paper,we present an efficient endto-end deep learning model for automatically detecting and removing specular highlights in a single image.In particular,an encoder–decoder network is utilized to detect specular highlights,and then a novel Unet-Transformer network performs highlight removal;we append transformer modules instead of feature maps in the Unet architecture.We also introduce a highlight detection module as a mask to guide the removal task.Thus,these two networks can be jointly trained in an effective manner.Thanks to the hierarchical and global properties of the transformer mechanism,our framework is able to establish relationships between continuous self-attention layers,making it possible to directly model the mapping between the diffuse area and the specular highlight area,and reduce indeterminacy within areas containing strong specular highlight reflection.Experiments on public benchmark and real-world images demonstrate that our approach outperforms state-of-the-art methods for both highlight detection and removal tasks. 展开更多
关键词 specular highlight detection specular highlight removal Unet-Transformer
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Characterization of somatic mutations of colorectal tumor in a patient with concurrent APC and MLH1 germline mutations
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作者 Yunsheng Cheng Yanyan Xu +10 位作者 xiaopeng zhang Jian Qi Jialiang Wang Yanzhe Liu Kun Wan YanWei Liu Liang Yu Hongzhi Wang Jinfu Nie Bo Hong Yong Wang 《Genes & Diseases》 SCIE CSCD 2023年第6期2245-2247,共3页
The two most common inherited forms of colorectal cancer(CRC)are familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.They are caused by germline mutations in the APC and mismatch repair genes,... The two most common inherited forms of colorectal cancer(CRC)are familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.They are caused by germline mutations in the APC and mismatch repair genes,respectively.1 The simultaneous inheritance of both an APC gene mutation and a mismatch repair gene mutation is very rare.In this study,we reported a coinheritance of mutations in the APC and MLH1 genes in a 20-year-old patient with CRC and multiple polyposes.We described for the first time the somatic mutational profile of a colorectal tumor harboring concurrent germline mutations in the APC and MLH1 genes. 展开更多
关键词 MLH1 COLORECTAL PATIENT
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压电智能结构拓扑优化研究进展 被引量:2
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作者 林晔 张晓鹏 +1 位作者 胡骏 亢战 《固体力学学报》 CAS CSCD 北大核心 2020年第5期391-408,共18页
压电材料因其变形精度高、反应速度快、易于制作成小型化元件已经被广泛应用于精密驱动、振动控制、精确定位等领域.改变压电智能结构中压电元器件的位置、大小、形状等参数能够有效地改善系统的力学性能,因而吸引了许多学者和工程师的... 压电材料因其变形精度高、反应速度快、易于制作成小型化元件已经被广泛应用于精密驱动、振动控制、精确定位等领域.改变压电智能结构中压电元器件的位置、大小、形状等参数能够有效地改善系统的力学性能,因而吸引了许多学者和工程师的关注和研究.拓扑优化作为有效的优化工具,已经成功应用于压电智能结构的优化设计中.论文首先阐述了压电智能结构拓扑优化的背景和意义,简要回顾了压电智能结构主动控制及分析方法,并综述了面向结构静变形控制的压电智能结构优化、面向振动控制的压电智能结构优化、压电俘能器的设计与优化等三个方面的研究进展.最后,简单归纳压电智能结构拓扑优化研究中值得关注的几个问题. 展开更多
关键词 拓扑优化 压电材料 智能结构 主动控制 结构优化
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Cas9/sgRNA递送技术及其研究进展 被引量:1
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作者 胡暄 王松 +2 位作者 于璐 张晓鹏 陈薇 《生物工程学报》 CAS CSCD 北大核心 2021年第11期3880-3889,共10页
在与CRISPR/Cas9基因编辑技术相关的临床应用中,Cas9/sgRNA的递送是决定基因编辑治疗效果的关键技术之一。无需转录和翻译过程的Cas9蛋白/sgRNA复合物直接递送形式可能能够提供更高的特异性和安全性。文中通过对Cas9/sgRNA递送技术的研... 在与CRISPR/Cas9基因编辑技术相关的临床应用中,Cas9/sgRNA的递送是决定基因编辑治疗效果的关键技术之一。无需转录和翻译过程的Cas9蛋白/sgRNA复合物直接递送形式可能能够提供更高的特异性和安全性。文中通过对Cas9/sgRNA递送技术的研究现状及其在基因相关疾病治疗中的进展进行简要综述,为新型药物载体的设计和基因治疗的临床应用提供新思路。 展开更多
关键词 Cas9/sg RNA递送 纳米载体 基因编辑 基因治疗
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A comparative study of Mn/CeO_2,Mn/ZrO_2 and Mn/Ce-ZrO_2 for low temperature selective catalytic reduction of NO with NH_3 in the presence of SO_2 and H_2O 被引量:31
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作者 Boxiong Shen xiaopeng zhang +2 位作者 Hongqing Ma Yan Yao Ting Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第4期791-800,共10页
Ce-ZrO2 is a widely used three-way catalyst support. Because of the large surface area and excellent redox quality, Ce-ZrO2 may have potential application in selective catalytic reduction (SCR) systems. In the prese... Ce-ZrO2 is a widely used three-way catalyst support. Because of the large surface area and excellent redox quality, Ce-ZrO2 may have potential application in selective catalytic reduction (SCR) systems. In the present work, Ce-ZrO2 was introduced into a low-temperature SCR system and CeO2 and ZrO2 supports were also introduced to make a contrastive study. Mn/CeO2, Mn/ZrO2 and Mn/Ce-ZrO2 were prepared by impregnating these supports with Mn(NO3)2 solution, and have been characterized by N2-BET, XRD, TPR, TPD, XPS, FT-IR and TG. The activity and resistance to SO2 and H2O of the catalysts were investigated. Mn/Ce-ZrO2 and Mn/CeO2 were proved to have better low-temperature activities than Mn/ZrO2, and yielded 98.6% and 96.8% NO conversion at 180℃, respectively. This is mainly because Mn/Ce-ZrO2 and Mn/CeO2 had higher dispersion of manganese oxides, better redox properties and more weakly adsorbed oxygen species than Mn/ZrO2. In addition, Mn/Ce-ZrO2 showed a good resistance to SO2 and H2O and presented 87.1% NO conversion, even under SO2 and H2O treatment for 6 hours, and the activity of Mn/Ce-ZrO2 was almost restored to its original level after cutting off the injection of SO2 and H2O. This was due to the weak water absorption and weak sulfation process on the surface of the catalyst. 展开更多
关键词 low temperature selective catalytic reduction MANGANESE Ce-ZrO2 SO2 poisoning
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Enhanced photocatalytic activity of Gd3+ doped TiO2 and Gd2O3 modified TiO2 prepared via ball milling method 被引量:6
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作者 Di Wu Chen Li +4 位作者 Dashuai zhang Lili Wang xiaopeng zhang Zaifeng Shi Qiang Lin 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第8期845-852,I0002,共9页
Gd^3+/TiO2 and Gd2O3/TiO2 nanoparticles were prepared by ball milling method.The effects of Gd^3+ion and Gd2O3 on the structure and optical property of TiO2 were studied by XRD and UV-vis DRS.Specific surface area was... Gd^3+/TiO2 and Gd2O3/TiO2 nanoparticles were prepared by ball milling method.The effects of Gd^3+ion and Gd2O3 on the structure and optical property of TiO2 were studied by XRD and UV-vis DRS.Specific surface area was determined by Brunauer-Emmett-Teller(BET)method.The morphology and elemental composition were characterized by SEM-EDS.XPS was used to determine the surface compositions and chemical character of elements.The sample sizes and microstructures were observed by TEM.The photocatalytic activities of TiO2 nanoparticles modified with rare earth metal gadolinium(Gd^3+ion or Gd2O3)were evaluated by degradation of methylene blue(MB)under UV light.Experimental results indicate that 2,5 mol%Gd^3+/TiO2 shows the best photocatalytic activity compared with Gd2O3/TiO2 and pure TiO2.The existence of gadolinium can exhibit the aggregation and induce lattice distortion of TiO2 obtained from XRD,SEM and TEM results.The band gap energy of 2.5 mol%Gd^3+/TiO2 decreases to3.07 eV and it leads to visible light absorption response which can be seen from UV-vis absorption spectra.The surface area of 2.5 mol%Gd^3+/TiO2 equals to 85.8 m^2/g and average crystal size is 21.1 nm.EDS and XPS analyses reveal that gadolinium can be introduced either into TiO2 lattice or adsorbed on the surface of TiO2.The content of surface OH groups in 2.5 mol%Gd^3+/TiO2 is 50,88%(1.55 times higher than that of pure TiO2)and the content of lattice oxygen decreases to 11.26%.The MB(25 mg/L)degradation reaction rate constants of 2,5 mol%Gd^3+/TiO2,0.5 mol%Gd2O3/TiO2 and pure TiO2 were0.0713,0.0588 and 0.0263 min^-1,respectively.The degradation rates of rhodamine B(30 mg/L)in 60 min are 97,9%,90.1%and 84.6%for 2,5 mol%Gd^3+/TiO2,0.5 mol%Gd2O3/TiO2 and pure TiO2,respectively. 展开更多
关键词 Ball milling METHOD Rare earth GADOLINIUM TiO2 METHYLENE blue
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Progress of Jinping Underground laboratory for Nuclear Astrophysics(JUNA) 被引量:3
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作者 WeiPing Liu ZhiHong Li +61 位作者 JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu zhang Hui zhang LiYong zhang NingTao zhang QiWei zhang Tao zhang xiaopeng zhang XueZhen zhang ZiMing zhang Wei Zhao Zuo Zhao Chao Zhou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第4期1-7,共7页
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire... Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 展开更多
关键词 核天体物理学 地下实验室 强流加速器 流体静压 演化过程 高灵敏度 ECR源 直接测量
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A proposed direct measurement of cross section at Gamow window for key reaction 19F(p,α) 16O in Asymptotic Giant Branch stars with a planned accelerator in CJPL 被引量:3
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作者 JianJun He ShiWei Xu +16 位作者 ShaoBo Ma Jun Hu LiYong zhang ChangBo Fu NingTao zhang Gang Lian Jun Su YunJu Li ShengQuan Yan YangPing Shen SuQing Hou BaoLu Jia Tao zhang xiaopeng zhang Bing Guo Shigeru Kubono WeiPing Liu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第5期76-82,共7页
In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nucle... In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ^(19)F( p,α)^(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions. 展开更多
关键词 核反应截面测量 直接测量 伽莫夫 国家自然科学基金委员会 恒星 巨星 窗户 加速器
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