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Detection and mitigation of RFI in SBRS observation data

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Research in Astronomy and Astrophysics 2021年第8期21卷 111-123页

作者： Zhen-Ping Qiang Jun cheng Zhen-Hong shang Kai-Fan Ji Fei Dai Hui Liu College of Big Data and Intelligent Engineering Southwest Forestry UniversityKunming 650224China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650504China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

In view of the inconsistency of channel gains and a large amount of interference noise in Solar Broadband Radio Spectrometer(SBRS) observation data,they will seriously affect the analysis of SBRS *** this paper,a method of Radio Frequency Interference(RFI) detection and mitigation for SBRS observation data is ***,the SBRS observation data are preprocessed,a part of the observation data was selected to calculate the mean and variance to achieve the normalization of the entire observation data,which can avoid the influence of strong noise on the normalization ***,we proposed an adaptive threshold RFI detection method based on fusion wavelet transform reconstruction and an RFI elimination method based on neighborhood weighted *** is worth mentioning that to detect RFI interference signals of different magnitudes,we adopted an iterative approach to the RFI detection and mitigation *** qualitative analysis of real observation data and quantitative analysis of simulated data,it is shown that the method proposed in this paper can effectively eliminate RFI in SBRS observation data,and improve the quality of observation data for further scientific analysis.

关键词： spectrographs:SBRS techniques:image processing and spectroscopic Sun:radio radiation

Microsurgical efficacy in 326 children with tethered cord syndrome: a retrospective analysis

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Neural Regeneration Research 2019年第1期14卷 149-155页

作者： Ai-Jia shang Chang-Hao Yang cheng cheng Ben-Zhang Tao Yuan-Zheng Zhang Hai-Hao Gao Shao-Cong Bai Department of Neurosurgery PLA General Hospital Department of Neurosurgery Yanan University Affiliated Hospital

Tethered cord syndrome is a progressive disease with a typically insidious onset in infants and children, and which can lead to persistent progress of neurological deficits and a high rate of disability without timely intervention. The purpose of this study was to investigate the curative effect of microsurgery in children with different types of tethered cord syndrome. In this study, we analyzed 326 patients with tethered cord syndrome, aged from 2 months to 14 years old, who were followed for 3-36 months after microscopic surgery. Based on clinical manifestations and imaging findings, these patients were classified into five types： tight ilium terminale （53 cases）, lipomyelome- ningocele （55 cases）, lipomatous malformation （124 cases）, postoperative adhesions （56 cases）, and split cord malformation （38 cases）. All patients underwent microsurgery. Curative effects were measured before and 3 months after surgery by Spina Bifida Neurological Scale based on sensory and motor functions, reflexes, and bladder and bowel function. The results showed that Spina Bifida Neurological Scale scores improved in all five types after surgery. Overall effective rates in these patients were 75%. Effective rates were 91% in tight ilium terminale, 84% in lipomyelomeningocele, 65% in lipomatous malformation, 75% in postoperative adhesion, and 79% in split cord mal- formation. Binary logistic regression analysis revealed that types of tethered cord syndrome （lipoma-type or not） and symptom duration before surgery were independent influencing factors of surgical outcome. These results show that therapeutic effect is markedly different in patients with different types of tethered cord syndrome. Suitable clinical classification for tethered cord syndrome will be helpful in predicting prognosis and guiding treatment. This trial has been registered in the Chinese Clinical Trial Registry （registration number： ChiCTR1800016464）.

关键词： nerve regeneration tethered cord syndrome surgery therapy prognosis children patients surgical outcome surgical methods prophylactic surgery spina bifida neural regeneration

Design of Micropipette System with High Precision for Small Enzyme Immunoassay Analyzer

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Journal of shanghai Jiaotong university(Science) 2019年第5期24卷 605-615页

作者： shang Zhiwu ZHOU Xiangping LI cheng ZHOU Xinyu School of Mechanical Engineering Tianjin Polytechnic University of China

A small auto micropipette system is developed to improve the reliability and accuracy of the automatic enzyme immunoassay analyzer’s microscale pipetting system. A sophisticated injection mechanism is designed by the means of dislocation parallel distribution of the screw and injector piston rod. It possesses the function of pipetting, taking and removing the pipette tips. In the control system, STM32 controller is used, controlling the single-axis S-type acceleration/deceleration algorithm and multi-threaded coordinated motion. The acceleration/deceleration curves are analyzed and optimized by using the method of segmentation;a minimum injection rate of 1 μL and a step rate of 0.05 μL are realized. The method of digital image processing is used to detect the amount of pipetting in micro-pipetting quantitatively. The liquid area is extracted by background contrast method, and the liquid volume in the tip is obtained by combining the geometric characteristics of the disposable tip, when the pipetting capacity is not qualified to carry out specific guidance on the pipetting system, and avoid the blocking needle, bubble and other abnormal pipetting phenomenon on the impact of pipetting accuracy. The experimental results show that the combination of the automatic sampling system and the image flow detection system can effectively improve the precision and reliability of the micro-pipetting system. Finally, the injection accuracy of the system at the test points with 10, 50 and 100 μL liquid volumes reaches 1.8%, 1.28% and 1.15%respectively.

关键词： enzyme immunoassay analyzer micropipette image processing motion control error compensation

Recent progress in third-generation low alloy steels developed under M^3 microstructure control

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 1-9页

作者： Zhen-jia Xie cheng-jia shang Xue-lin Wang Xue-min Wang Gang Han Raja-devesh-kumar Misra Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX 79968USA

During the past thirty years, two generations of low alloy steels(ferrite/pearlite followed by bainite/martensite) have been developed and widely used in structural applications. The third-generation of low alloy steels is expected to achieve high strength and improved ductility and toughness, while satisfying the new demands for weight reduction, greenness, and safety. This paper reviews recent progress in the development of third-generation low alloy steels with an M^3 microstructure, namely, microstructures with multi-phase, meta-stable austenite, and multi-scale precipitates. The review summarizes the alloy designs and processing routes of microstructure control, and the mechanical properties of the *** stabilization of retained austenite in low alloy steels is especially emphasized. Multi-scale nano-precipitates, including carbides of microalloying elements and Cu-rich precipitates obtained in third-generation low alloy steels, are then introduced. The structure–property relationships of third-generation alloys are also discussed. Finally, the promises and challenges to future applications are explored.

关键词： third-generation low alloy steels multi-phase microstructure meta-stable retained austenite multi-scale precipitates

N-Doped porous carbon supported palladium nanoparticles as a highly efficient and recyclable catalyst for the Suzuki coupling reaction

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Chinese Chemical Letters 2016年第1期27卷 149-154页

作者： Li Zhang Wen-Huan Dong Ning-Zhao shang cheng Feng Shu-Tao Gao Chun Wang College of Science Agricultural University of Hebei

A new catalyst, Pd particles supported on the N-doped porous carbon（PC） derived from Zn-based metal-organic frameworks（zeolitic imidazolate framework： ZIF-8）, was successfully prepared for the first *** as-prepared catalyst was designated as N-doped PC-Pd, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscope, N_2 adsorption and inductively coupled plasma atomic emission spectroscopy. The N-doped PC-Pd composite exhibited high catalytic activity toward the Suzuki-Miyaura cross-coupling reactions. The yields of the products were in the range of 90%-99%. The catalyst could be readily recycled and reused at least 6 consecutive cycles without a significant loss of its catalytic activity.

关键词： Suzuki-Miyaura coupling reaction Pd catalyst N-Doped nanoporous carbon Metal-organic frameworks

Synthetic Strategies of Carbon Nanobelts and Beyond

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Chemical Research in Chinese Universities 2024年第4期40卷 627-631页

作者： LI Yanbang shang Wansong REN Yu ZHANG Xi-Sha LI cheng ZHANG Guanxin ZHANG Deqing Beijing National Laboratory for Molecular Science CAS Key Laboratory for Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Carbon nanobelts(CNBs)with aesthetically appealing molecular structures and outstanding physical properties have attracted more and more attentions from the scientific community due to their potential applications in synthetic materials,host-guest chemistry,optoelectronics,and so *** synthesis of CNBs at different stages was overviewed and some representative breakthroughs and advances in synthetic strategies were highlighted and *** key issue for the synthesis of CNBs is how to construct curved structures with high strain *** not only proposed a few unconventional CNBs as the promising target molecules,but also pointed out the bottom-up synthesis of conjugated tubular segments of carbon nanotubes sharing similar properties as carbon nanotubes is the next focus in this emerging area.

关键词： Carbon nanobelt Strain energy Carbon nanoring Single-walled carbon nanotube Bottom-up synthesis

Study on disulfur-backboned nucleic acids:Part Ⅳ.Efficient synthesis of 3',5'-dithio-2'-deoxyguanosine

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Chinese Chemical Letters 2010年第2期21卷 131-134页

作者： Pei Hua shang Chang Mei cheng Hua Wang Hong Chao Zheng Yu Fen Zhao Key Laboratory of Phosphorus and Chemical Biology the Ministry of EducationDepartment of ChemistryTsinghua UniversityBeijing 10084China

An efficient and novel method for synthesizing 3′,5′-dithio-2′-deoxyguanosine was *** this method normal guanosine was used as the starting material.A very efficient procedure was used to synthesize 2-O-tosylguanosine 1,which used 0.1 *** instead of 2 eq.1 was treated with LTBH to give 9-(2-deoxy-β-D-threo-pentofuranosyl)guanine 2.2 could be easily turned to the target compound.

关键词： 3′,5′-Dithio-2′-deoxyguanosine Guanosine Synthesis

Characterization of carotenoid biosynthetic pathway genes in the pea aphid(Acyrthosiphon pisum)revealed by heterologous complementation and RNA interference assays

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Insect Science 2022年第3期29卷 645-656页

作者： Bi-Yue Ding Xiu-cheng Xie Feng shang Guy Smagghe Jin-Zhi Niu Jin-Jun Wang Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina International Joint Laboratory of China-Belgium on Sustainable Crop Pest ControlAcademy of Agricultural SciencesSouthwest UniversityChongqingChina Department of Plants and Crops Faculty of Bioscience EngineeringGhent UniversityGhentBelgium

Carotenoids are involved in many essential physiological functions and are produced from geranylgeranyl pyrophosphate through synthase,desaturase,and cyclase *** the pea aphid(Acyrthosiphon pisum),the duplication of carotenoid biosynthetic genes,including carotenoid synthases/cyclases(ApCscA-C)and desaturases(ApCdeA-D),through horizontal gene transfer from fungi has been detected,and ApCdeB has known dehydrogenation ***,whether other genes contribute to aphid carotenoid biosynthesis,and its specific regulatory pathway,remains *** the current study,functional analyses of seven genes were performed using heterologous complementation and RNA interference *** bifunctional enzymes ApCscA-C were responsible for the synthase of phytoene,and ApCscC may also have a cyclase ***,ApCdeC,and ApCdeD had diverse dehydrogenation *** catalyzed the enzymatic conversion of phytoene to neurosporene(three-step product),ApCdeC catalyzed the enzymatic conversion of phytoene to ζ-carotene(two-step product),and ApCdeD catalyzed the enzymatic conversion of phytoene to lycopene(four-step product).Silencing of ApCscs reduced the expression levels of ApCdes,and silencing these carotenoid biosynthetic genes reduced the α-,β-,and γ-carotene levels,as well as the total carotenoid *** results suggest that these genes were activated and led to carotenoid biosynthesis in the pea aphid.

关键词： carotenoid biosynthesis heterologous complementary pea aphid RNA interference

Overexpression of SOS Genes Enhanced Salt Tolerance in Sweetpotato

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Journal of Integrative Agriculture 2012年第3期11卷 378-386页

作者： GAO shang YUAN Li ZHAI Hong LIU cheng-long HE Shao-zhen LIU Qing-chang Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization Ministry of Education/College of Agriculture and BiotechnologyChina

The production of transgenic sweetpotato （*** 18） plants exhibiting enhanced salt tolerance using salt overly sensitive （SOS） genes was achieved through Agrobacterium tumefaciens-mediated *** strain EHA105 harbors a binary vector pCAMBIA3301 with SOS genes （SOS1,SOS2 and SOS3） and bar *** culture was conducted using 0.3 mg L^-1 phosphinothricin （PPT）.A total of 40 plants were produced from the inoculated 170 cell aggregates via somatic *** analysis showed that 37 of the 40 regenerated plants were transgenic *** in vitro assay demonstrated that superoxide dismutase （SOD） and proline were significantly more accumulated and malonaldehyde （MDA） was significantly less accumulated in 21 transgenic plants than in control plants when they were exposed to 86 mmol L^-1 *** tolerance of these 21 plants was further evaluated with Hoagland solution containing 0,51,86,and 120 mmol L^-1 NaCl in the *** results indicated that 6 of them had significantly better growth and rooting ability than the remaining 15 transgenic plants and control *** of SOS genes in the 6 salt-tolerant transgenic plants was demonstrated by RT-PCR *** study provides an alternative approach for improving salt tolerance of sweetpotato.

关键词： Agrobacterium tumefaciens sweetpotato salt tolerance SOS transgenic plant