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基于S3C2410的GPRS数据终端的设计

孙学用

《中国工程科学》 2007年 第9卷 第12期   页码 94-96

摘要: 提出了以S3C2410处理器为核心,以SIM100-E为GPRS通信模块,构建了一套嵌入式Internet数据终端的方案,对其硬件构成及工作流程进行了讨论,描述了其软件层次结构,并详细讲解了基于该平台的

关键词: GPRS;嵌入式Internet;S3C2410;SIM100-E    

基于最大密度的小型无人机电机速度估计与故障检测 Research Articles

Jefferson S. SOUZA1,Moises C. BEZERRIL1,Mateus A. SILVA1,Frank C.VERAS2,Abel LIMA-FILHO3,Jorge Gabriel RAMOS4,Alisson V. BRITO1

《信息与电子工程前沿(英文)》 2021年 第22卷 第7期   页码 1002-1009 doi: 10.1631/FITEE.2000149

摘要: 介绍了基于混沌的最大密度信号分析技术在无刷直流电机分析中的应用。利用了从电流信号最大密度估计得出的相关系数。通过实验实现了无刷电机在试验台上的速度估计以及在小型无人机上的故障检测。实验结果表明,在97.8%的案例中可估计电机速度,在82.75%的分析案例中可检测故障。

关键词: 无人机;速度识别;故障检测;混沌    

Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for CC coupling and electrocatalytic

《化学科学与工程前沿(英文)》 2022年 第16卷 第10期   页码 1514-1525 doi: 10.1007/s11705-022-2158-y

摘要: The current work describes the synthesis of a new bio-waste derived cellulosic-carbon supported-palladium nanoparticles enriched magnetic nanocatalyst (Pd/Fe3O4@C) using a simple multi-step process under aerobic conditions. Under mild reaction conditions, the Pd/Fe3O4@C magnetic nanocatalyst demonstrated excellent catalytic activity in the Hiyama cross-coupling reaction for a variety of substrates. Also, the Pd/Fe3O4@C magnetic nanocatalyst exhibited excellent catalytic activity up to five recycles without significant catalytic activity loss in the Hiyama cross-coupling reaction. Also, we explored the use of Pd/Fe3O4@C magnetic nanocatalyst as an electrocatalyst for hydrogen evolution reaction. Interestingly, the Pd/Fe3O4@C magnetic nanocatalyst exhibited better electrochemical activity compared to bare carbon and magnetite (Fe3O4 nanoparticles) with an overpotential of 293 mV at a current density of 10 mA·cm–2.

关键词: bio-waste     cellulosic-carbon     Pd/Fe3O4     Hiyama cross-coupling     hydrogen evolution reaction     recyclability    

New Editors-in-Chief’s Message

Jiming HAO,John C. CRITTENDEN

《环境科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 1-1 doi: 10.1007/s11783-015-0767-0

Novel mutation c.1210-3C>G in with a poly-T tract of 5T affects mRNA splicing in a Chinese patient

《医学前沿(英文)》 2022年 第16卷 第1期   页码 150-155 doi: 10.1007/s11684-021-0846-5

摘要: Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G>A, p.Gly970Asp in exon 18 and c.1210-3C>G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C>G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C>G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

关键词: cystic fibrosis     CFTR     splicing mutation     minigene    

GO-modified flexible polymer nanocomposites fabricated via 3D stereolithography

Chi Him Alpha Tsang, Adilet Zhakeyev, Dennis Y.C. Leung, Jin Xuan

《化学科学与工程前沿(英文)》 2019年 第13卷 第4期   页码 736-743 doi: 10.1007/s11705-019-1836-x

摘要: Graphene oxide (GO) induced enhancement of elastomer properties showed a great deal of potential in recent years, but it is still limited by the barrier of the complicated synthesis processes. Stereolithography (SLA), used in fabrication of thermosets and very recently in “flexible” polymers with elastomeric properties, presents itself as simple and user-friendly method for integration of GO into elastomers. In this work, it was first time demonstrated that GO loadings can be incorporated into commercial flexible photopolymer resins to successfully fabricate GO/elastomer nanocomposites via readily accessible, consumer-oriented SLA printer. The material properties of the resulting polymer was characterized and tested. The mechanical strength, stiffness, and the elongation of the resulting polymer decreased with the addition of GO. The thermal properties were also adversely affected upon the increase in the GO content based on differential scanning calorimetry and thermogravimetric analysis results. It was proposed that the GO agglomerates within the 3D printed composites, can result in significant change in both mechanical and thermal properties of the resulting nanocomposites. This study demonstrated the possibility for the development of the GO/elastomer nanocomposites after the optimization of the GO/“flexible” photoreactive resin formulation for SLA with suitable annealing process of the composite in future.

关键词: graphene oxide     polymer     flexible     3D printing     stereolithography    

In-MOF-derived In2S3/Bi2S3 heterojunction for enhanced photocatalytic

《能源前沿(英文)》 2023年 第17卷 第5期   页码 654-663 doi: 10.1007/s11708-023-0885-5

摘要: Transition metal sulfides are commonly studied as photocatalysts for water splitting in solar-to-fuel conversion. However, the effectiveness of these photocatalysts is limited by the recombination and restricted light absorption capacity of carriers. In this paper, a broad spectrum responsive In2S3/Bi2S3 heterojunction is constructed by in-situ integrating Bi2S3 with the In2S3, derived from an In-MOF precursor, via the high-temperature sulfidation and solvothermal methods. Benefiting from the synergistic effect of wide-spectrum response, effective charge separation and transfer, and strong heterogeneous interfacial contacts, the In2S3/Bi2S3 heterojunction demonstrates a rate of 0.71 mmol/(g∙h), which is 2.2 and 1.7 times as much as those of In2S3 (0.32 mmol/(g∙h) and Bi2S3 (0.41 mmol/(g∙h)), respectively. This paper provides a novel idea for rationally designing innovative heterojunction photocatalysts of transition metal sulfides for photocatalytic hydrogen production.

关键词: photocatalytic hydrogen production     wide-spectrum response     metal sulfides     MOFs derivative     heterogeneous interfacial contact    

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

《医学前沿(英文)》 2023年 第17卷 第1期   页码 143-155 doi: 10.1007/s11684-022-0929-y

摘要: Gliomas are the most common central nervous system tumours; they are highly aggressive and have a poor prognosis. RGS16 belongs to the regulator of G-protein signalling (RGS) protein family, which plays an important role in promoting various cancers, such as breast cancer, pancreatic cancer, and colorectal cancer. Moreover, previous studies confirmed that let-7c-5p, a well-known microRNA, can act as a tumour suppressor to regulate the progression of various tumours by inhibiting the expression of its target genes. However, whether RGS16 can promote the progression of glioma and whether it is regulated by miR let-7c-5p are still unknown. Here, we confirmed that RGS16 is upregulated in glioma tissues and that high expression of RGS16 is associated with poor survival. Ectopic deletion of RGS16 significantly suppressed glioma cell proliferation and migration both in vitro and in vivo. Moreover, RGS16 was validated as a direct target gene of miR let-7c-5p. The overexpression of miR let-7c-5p obviously downregulated the expression of RGS16, and knocking down miR let-7c-5p had the opposite effect. Thus, we suggest that the suppression of RGS16 by miR let-7c-5p can promote glioma progression and may serve as a potential prognostic biomarker and therapeutic target in glioma.

关键词: RGS16     let-7c-5p     glioma     proliferation     migration    

Uncertainty propagation analysis by an extended sparse grid technique

JIA, C. JIANG, C. M. FU, B. Y. NI, C. S. WANG, M. H. PING

《机械工程前沿(英文)》 2019年 第14卷 第1期   页码 33-46 doi: 10.1007/s11465-018-0514-x

摘要: In this paper, an uncertainty propagation analysis method is developed based on an extended sparse grid technique and maximum entropy principle, aiming at improving the solving accuracy of the high-order moments and hence the fitting accuracy of the probability density function (PDF) of the system response. The proposed method incorporates the extended Gauss integration into the uncertainty propagation analysis. Moreover, assisted by the Rosenblatt transformation, the various types of extended integration points are transformed into the extended Gauss-Hermite integration points, which makes the method suitable for any type of continuous distribution. Subsequently, within the sparse grid numerical integration framework, the statistical moments of the system response are obtained based on the transformed points. Furthermore, based on the maximum entropy principle, the obtained first four-order statistical moments are used to fit the PDF of the system response. Finally, three numerical examples are investigated to demonstrate the effectiveness of the proposed method, which includes two mathematical problems with explicit expressions and an engineering application with a black-box model.

关键词: uncertainty propagation analysis     extended sparse grid     maximum entropy principle     extended Gauss integration     Rosenblatt transformation     high-order moments analysis    

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1986-2000 doi: 10.1007/s11705-023-2337-5

摘要: Breakage of the C–N bond is a structure sensitive process, and the catalyst size significantly affects its activity. On the active metal nanoparticle scale, the role of catalyst size in C–N bond cleavage has not been clearly elucidated. So, Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature, and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C–N bond hybridization patterns as reactants. Results showed a 13 times higher reaction rate for sp3-hybridized C–N bond cleavage than sp2-hybridized C–N bond cleavage, while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size increased. Different concentrations of terrace, step, and corner sites were found in different sizes of Ru nanoparticles. The relationship between catalytic site variation and C–N bond cleavage activity was further investigated by calculating the turnover frequency values for each site. This analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C–N bond cleavage activity, and the step atoms are the active sites for the C–N bond cleavage. When Ru nanoparticles are smaller than 1.9 nm, they have a strong adsorption effect on the reactants, which will affect the catalytic performance of the Ru catalyst. Furthermore, these findings were also confirmed on other metallic Pd/Pt catalysts. The role of step sites in C–N bond cleavage was proposed using the density function theory calculations. The reactants have stronger adsorption energies on the step atoms, and step atoms have d-band center nearer to the Fermi level. In this case, the interaction with the reactant is stronger, which is beneficial for activating the C–N bond of the reactant.

关键词: sp3/sp2-hybridized C–N bond     noble metal nanoparticle     catalytic active site     turnover frequency     DFT    

基于2013年、2015年和2017年星载BDS/GPS观测数据的FY-3C卫星精密轨道确定 Article

李星星, 张柯柯, 孟祥广, 张伟, 张倩, 张小红, 李昕

《工程(英文)》 2020年 第6卷 第8期   页码 904-912 doi: 10.1016/j.eng.2019.09.001

摘要:

本文基于2013—2017年FY-3C卫星星载BDS和GPS观测数据,研究了星载BDS的定轨性能及其对低轨卫星精密定轨的贡献。2013年、2015年和2017年的FY-3C卫星单GPS定轨的重叠轨道差异平均一维均方根(1D RMS)分别为2.0 cm、1.7 cm和1.5 cm。由于BDS二代区域系统和FY-3C较少的BDS跟踪通道,FY-3C卫星单BDS定轨的精度要远差于单GPS定轨,其2013年、2015年和2017年重叠轨道1D RMS分别为150.9 cm、115.0对于BDS+GPS (GC)双系统定轨,FY-3C卫星在2013年、2015年和2017年的重叠轨道精度分别为2.5 cm、2.3 cm和1.6 cm。得益于近年来IGS精密轨道钟差产品精度的不断提高,特别是2015年高采样率(30 s采样间隔)卫星钟差产品的发布,FY-3C卫星的单BDS和GC双系统定轨精度从2013年开始逐步提高。

关键词: 风云-3C     低轨卫星精密定轨     星载BDS/GPS     BDS码偏差     BDS/GPS双系统定轨    

3S技术在区域生态功能区划中的应用——以河南省濮阳市为案例

卞有生,蔡博峰,赵楠

《中国工程科学》 2005年 第7卷 第12期   页码 54-60

摘要:

生态功能区划是区域社会经济协调发展的基础性工作,3S技术则是保证区划科学与准确的重要技术手段。以河南省濮阳市为例,介绍了3S技术在区域生态功能区划中的应用及其优势与特点,即数据的准确性、现势性和科学性得到进一步提高,而且空间分析功能充分实现了不同权重生态因子的叠加,同时在区划过程中充分考虑生态格局对生态功能的影响

关键词: 生态功能区划     3S     空间分析     生态格局    

Durability of plasma-sprayed Cr3C2-NiCr coatings under rolling contact conditions

Xiancheng ZHANG, Fuzhen XUAN, Shantung TU, Binshi XU, Yixiong WU

《机械工程前沿(英文)》 2011年 第6卷 第1期   页码 118-135 doi: 10.1007/s11465-011-0127-0

摘要:

The aim of this paper was to address the rolling contact fatigue (RCF) failure mechanisms of plasma-sprayed Cr3C2-NiCr coatings under different tribological conditions of contact stress. Weibull distribution plots of fatigue lives of the coated specimens at different contact stresses were obtained. The failure modes of coatings were identified on the basis of wore surface observations of the failed coatings. Results showed that the RCF failure modes can be classified into four main categories, i.e., surface abrasion, spalling, cohesive delamination, and interfacial delamination. The probabilities of the surface abrasion and spalling type failures were relatively high at low contact stress. When the coatings were subjected to abrasion and spalling type failures, the failure of the coating was depended on the microstrcture of the coating. The stress concentration near the micro-defects in the coating may be the may reason for the formation of spall. The coatings were prone to fail in delamination under higher contact stresses. However, the delamination of coating may be related to distribution of shear stress amplitude within coating. The location of maximum shear stress amplitude can be used as a key parameter to predict the initiation of subsurface cracks within coating in rolling contact.

关键词: rolling contact fatigue     coating     Weibull distribution     failure mode     mechanism    

基于半实物的S频段卫星测控仿真系统平台设计

杨永安,韩忠民,冯祖仁,李光明,张宏伟

《中国工程科学》 2004年 第6卷 第12期   页码 85-90

摘要: 根据航天测控系统和S频段测控设备的特点,明确了仿真系统的组成及功能,并对主要部分进行了详细的描述;确定了仿真系统运行工作模式、主要技术指标、接口之间关系;结合实际应用情况,通过与真星进行比对,证明通过建立半物理仿真数学模型

关键词: 系统仿真     航天     测控系统     S频段     卫星    

过硫酸盐诱导的缺陷氮化碳中三配位氮(N3C)空位增强光催化产过氧化氢 Article

缪蔚, 王奕杰, 刘莹, 秦贺贺, 褚成成, 毛舜

《工程(英文)》 2023年 第25卷 第6期   页码 214-221 doi: 10.1016/j.eng.2021.12.016

摘要: 其中石墨氮化碳(g-C3N4)被认为是最有前途的合成过氧化氢的光催化剂之一;并且,在g-C3N4中引入氮空位已被证明是提高其光催化活性的有效策略在此,本文提出了一种简便的过硫酸钠共晶聚合方法,制备了具有丰富三配位氮空位(N3C)的g-C3N4。本研究的结果表明,在g-C3N4中引入N3C空位可以成功地拓宽光吸收范围,抑制光激发电荷的重组,增强O2的吸附和活化富含N3C空位的g-C3N4的光催化过氧化氢产量是原始g-C3N4的4.5倍。本研究提出了在g-C3N4中引入N3C空位的新策略,为开发光催化产过氧化氢的活性催化剂提供了一种新方法。

关键词: 氮化碳     N3C空位     过氧化氢     光催化     过硫酸盐    

标题 作者 时间 类型 操作

基于S3C2410的GPRS数据终端的设计

孙学用

期刊论文

基于最大密度的小型无人机电机速度估计与故障检测

Jefferson S. SOUZA1,Moises C. BEZERRIL1,Mateus A. SILVA1,Frank C.VERAS2,Abel LIMA-FILHO3,Jorge Gabriel RAMOS4,Alisson V. BRITO1

期刊论文

Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for CC coupling and electrocatalytic

期刊论文

New Editors-in-Chief’s Message

Jiming HAO,John C. CRITTENDEN

期刊论文

Novel mutation c.1210-3C>G in with a poly-T tract of 5T affects mRNA splicing in a Chinese patient

期刊论文

GO-modified flexible polymer nanocomposites fabricated via 3D stereolithography

Chi Him Alpha Tsang, Adilet Zhakeyev, Dennis Y.C. Leung, Jin Xuan

期刊论文

In-MOF-derived In2S3/Bi2S3 heterojunction for enhanced photocatalytic

期刊论文

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

期刊论文

Uncertainty propagation analysis by an extended sparse grid technique

JIA, C. JIANG, C. M. FU, B. Y. NI, C. S. WANG, M. H. PING

期刊论文

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

期刊论文

基于2013年、2015年和2017年星载BDS/GPS观测数据的FY-3C卫星精密轨道确定

李星星, 张柯柯, 孟祥广, 张伟, 张倩, 张小红, 李昕

期刊论文

3S技术在区域生态功能区划中的应用——以河南省濮阳市为案例

卞有生,蔡博峰,赵楠

期刊论文

Durability of plasma-sprayed Cr3C2-NiCr coatings under rolling contact conditions

Xiancheng ZHANG, Fuzhen XUAN, Shantung TU, Binshi XU, Yixiong WU

期刊论文

基于半实物的S频段卫星测控仿真系统平台设计

杨永安,韩忠民,冯祖仁,李光明,张宏伟

期刊论文

过硫酸盐诱导的缺陷氮化碳中三配位氮(N3C)空位增强光催化产过氧化氢

缪蔚, 王奕杰, 刘莹, 秦贺贺, 褚成成, 毛舜

期刊论文