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Single DNA Condensation Induced by Hexammine Cobalt with Molecular Combing
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作者 Gao-ming Hu Yu Lin +2 位作者 Shi-yong Ran Ya n-wei Wang Guang-can Yang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第3期359-364,374,共7页
We investigated the interaction between DNA and hexammine cobalt III [Co(NH3)6]3+ by a simple molecular combing method and dynamic light scattering. The average extension of A- DNA-YOYO-1 complex is found to be 20.... We investigated the interaction between DNA and hexammine cobalt III [Co(NH3)6]3+ by a simple molecular combing method and dynamic light scattering. The average extension of A- DNA-YOYO-1 complex is found to be 20.9μm, about 30% longer than the contour length of the DNA in TE buffer (10 mmol/L Tris, 1 mmol/L EDTA, pH=8.0), due to bis-intercalation of YOYO-1. A multivalent cation, hexammine cobalt, is used for DNA condensation. We find that the length of DNA-[Co(NH3)6]3+ complexes decrease from 20.9 μm to 5.9μm as the concentration of the [Co(NH3)6]3+ vary from 0 to 3 μmol/L. This observation provides a direct visualization of single DNA condensation induced by hexammine cobalt. The results from the molecular combing studies are supported by dynamic light scattering investigation, where the average hydrodynamic radius of the DNA complex decreases from 203.8 nm to 39.26 nm under the same conditions. It shows that the molecular combing method is feasible for quantitative conformation characterization of single bio-macromolecules. 展开更多
关键词 Molecular combing Hexammine cobalt CONDENSATION Dynamic light scatter-ing Fluorescent microscopy
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THE INFLUENCE OF COMBING ROLLER SPEED ON PURE RAMIE NOIL ROTOR YARN QUALITY AND SPINNING PERFORMANCE
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作者 林廷坤 黄秀宝 《Journal of China Textile University(English Edition)》 EI CAS 1994年第2期19-21,25-26,共5页
This paper reports the optimum design of combing roller speed with reference to yielding 6-13 Ne(98.4—45.4 tex) pure ramie noil rotor-spun yarns. The universal rotatable composite design is adopted to get the highly ... This paper reports the optimum design of combing roller speed with reference to yielding 6-13 Ne(98.4—45.4 tex) pure ramie noil rotor-spun yarns. The universal rotatable composite design is adopted to get the highly precise regression equations, in which the variables are combing roller speed and yarn linear density considered to be the main technological parameters of combing roller and, the responses are the evaluation indexes concerning spinning stability, fiber length distribution of fibre ring from rotor groove and yarn properties. Based on these regression equations, the contours are plotted to analyse the influences of the parameters on the evaluation indexes; the optimization multicriteria mathematical model is simultaneously established to obtain the optimum parameters with the aid of Object Programming Approach along with Constrained Random Ray Method. Finally, an experiment is carried out to further test the acceptance of the calculated optimum values. It is shown that, for any yarn linear density within 6—13 Ne (98.4—45.4 tex), combing roller speed varying from 5000 to 9150 r/min affects content of extra-long fibre in fibre ring from rotor groove and yarn properties but does not significantly influence spinning stability; 7075 r/min, at which the SAQ-12 type of saw-toothed combing roller runs, is recommended to be the optimum combing roller speed for producing 6—13 Ne (98.4—45.4 tex) pure ramie noil yarns, where a compromise is achieved among the lowest content of extra-long fibre in fibre ring, the best spinning stability and the best yarn properties. 展开更多
关键词 ramie combing ROLLERS RAMIE noil rotor spinning TECHNOLOGICAL parameters optimum design.
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FUZZY DECISION-MAKING OF COMBING ROLLER COVERING FOR SPINNING PURE RAMIE NOIL ROTOR-SPUN YARNS
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作者 黄秀宝 林廷坤 《Journal of China Textile University(English Edition)》 EI CAS 1993年第1期1-9,共9页
This paper deals with the types and specifications of combing roller covering for spinning pureramie noil rotor-spun yarns.A handling mode combining Fuzzy Decision-making and FuzzyCluster Analysis has been used for an... This paper deals with the types and specifications of combing roller covering for spinning pureramie noil rotor-spun yarns.A handling mode combining Fuzzy Decision-making and FuzzyCluster Analysis has been used for analyzing the experimental results.It is shown that,with regard to the specifications of the sawtooth clothing of the combing rol-ler,large working angle,large tooth pitch,fine tooth shape,short tooth height,smooth finish andgood wearability are of benefit to improving the spinning stability and the spun yarn properties.The pinned combing roller,however,regardless of its complicated process of production,is sug-gested to be preferred for spinning the pure ramie noil rotor-spun yarns.The handling mode used in this work is efficient in improving the reliability and objectivity ofthe conclusions and can be used for solving the similar problems. 展开更多
关键词 RAMIE combing rollers metallic clothing FUZZY decision FUZZY cluster analysis RAMIE NOIL rotor SPINNING
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Study of the Application of PPG-5-CETETH-20 in Personal Care Rinse-off Product
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作者 Chen Dongzhi Li Zhenzhen Xu Mingli 《China Detergent & Cosmetics》 CAS 2024年第1期39-44,共6页
PPG-5-Ceteth-20 is a multifunction raw material.PPG-5-Ceteth-20 has a wide range of application in skin care and hair care products.The purpose of this study was to evaluate the performance of PPG-5-Ceteth-20.The resu... PPG-5-Ceteth-20 is a multifunction raw material.PPG-5-Ceteth-20 has a wide range of application in skin care and hair care products.The purpose of this study was to evaluate the performance of PPG-5-Ceteth-20.The results shown that PPG-5-Ceteth-20 can improve hair combing,softness and smoothing in the hair care product.In additional,it can improve foam stability and compactness,and it doesn’t affect the transparency of the hair care product. 展开更多
关键词 PPG-5-Ceteth-20 combing SOFTNESS MULTIFUNCTION
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Third-order nonlinear wavelength conversion in chalcogenide glass waveguides towards mid-infrared photonics
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作者 Fengbo Han Jiaxin Gu +7 位作者 Lu Huang Hang Wang Yali Huang Xuecheng Zhou Shaoliang Yu Zhengqian Luo Zhipeng Dong Qingyang Du 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期269-274,共6页
The increasing demand in spectroscopy and sensing calls for infrared(mid-IR)light sources.Here,we theoretically investigate nonlinear wavelength conversion of Ge_(28)Sb_(12)Se_(60)chalcogenide glass waveguide in the m... The increasing demand in spectroscopy and sensing calls for infrared(mid-IR)light sources.Here,we theoretically investigate nonlinear wavelength conversion of Ge_(28)Sb_(12)Se_(60)chalcogenide glass waveguide in the mid-IR spectral regime.With waveguide dispersion engineering,we predict generation of over an octave wavelength(2.8μm-5.9μm)tuning range Raman soliton self-frequency shift,over 2.5 octaves wavelength cover range supercontinuum(1.2μm-8.0μm),as well as single soliton Kerr comb generated in suspended Ge_(28)Sb_(12)Se_(60)waveguide.Our findings evidenced that Ge_(28)Sb_(12)Se_(60)chalcogenide glass waveguides can simultaneously satisfy the generation of Raman soliton self-frequency shift,supercontinuum spectrum,and Kerr frequency comb generation through dispersion engineering towards mid-IR on chip. 展开更多
关键词 chalcogenide glass Raman soliton self-frequency shift SUPERCONTINUUM soliton Kerr comb
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Frequency-modulated continuous-wave multiplexed gas sensingbased on optical frequency comb calibration
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作者 Linhua Jia Xinghua Qu Fumin Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期152-163,共12页
Laser absorption spectroscopy has proven to be an effective approach for gas sensing, which plays an important rolein the fields of military, industry, medicine and basic research. This paper presents a multiplexed ga... Laser absorption spectroscopy has proven to be an effective approach for gas sensing, which plays an important rolein the fields of military, industry, medicine and basic research. This paper presents a multiplexed gas sensing system basedon optical frequency comb (OFC) calibrated frequency-modulated continuous-wave (FMCW) tuning nonlinearity. Thesystem can be used for multi-parameter synchronous measurement of gas absorption spectrum and multiplexed opticalpath. Multi-channel parallel detection is realized by combining wavelength division multiplexing (WDM) and frequencydivision multiplexing (FDM) techniques. By introducing nonlinear optical crystals, broadband spectrum detection is simultaneouslyachieved over a bandwidth of hundreds of nanometers. An OFC with ultra-high frequency stability is used asthe frequency calibration source, which guarantees the measurement accuracy. The test samples involve H13C14N, C_(2)H_(2)and Rb vapor cells of varying densities and 5 parallel measurement experiments are designed. The results show that themeasurement accuracies of spectral absorption line and the optical path are 150 MHz and 20 m, respectively. The schemeoffers the advantages of multiplexed, multi-parameter, wide spectrum and high resolution detection, which can realize theidentification of multi-gas components and the high-precision inversion of absorption lines under different environments.The proposed sensor demonstrates great potential in the field of high-resolution absorption spectrum measurement for gassensing applications. 展开更多
关键词 frequency-modulated continuous-wave(FMCW)technology optical frequency comb MULTIPLEXING absorption spectroscopy
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Mid-infrared Optical Frequency Comb-based Fourier Transform Spectrometer for Broadband Molecular Spectroscopy
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作者 Feihu Cheng Weixiong Zhao +5 位作者 Bo Fang Nana Yang Shuangshuang Li Weijun Zhang Lunhua Deng Weidong Chen 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期471-480,I0093,共11页
Optical frequency combbased Fourier transform spectroscopy has the features of broad spectral bandwidth,high sensitivity,andmultiplexed trace gas detection,which has valuable application potential in the fields of pre... Optical frequency combbased Fourier transform spectroscopy has the features of broad spectral bandwidth,high sensitivity,andmultiplexed trace gas detection,which has valuable application potential in the fields of precision spectroscopy and trace gas detection.Here,we report the development of a mid-infrared Fourier transform spectrometer based on an optical frequency comb combined with a Herriott-type multipass cell.Using this instrument,the broadband absorption spectra of several important molecules,including methane,acetylene,water molecules and nitrous oxide,are measured by near real-time data acquisition in the 2800-3500 cm^(-1)spectral region.The achieved minimum detectable absorption of the instrument is 4.4×10^(-8)cm^(-1)·Hz^(-1/2)per spectral element.Broadband spectra of H_(2)0 are fited using the Voigt profile multispectral fitting technique and the consistency of the concentration inversion is 1%.Our system also enables precise spectroscopic measurements,and it allows the determination of the spectral line positions and upper state constants of N_(2)O in the(0002)-(1000)band,with results in good agreement with those reported by Toth[Appl.Opt.30,5289(1991)]. 展开更多
关键词 Mid-infrared optical frequency comb Multi-pass cell Fourier transform infrared spectrometer
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Optical frequency comb technology: from ground to space
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作者 Xiaodong Shao Yu Yan +1 位作者 Hainian Han Zhiyi Wei 《Astronomical Techniques and Instruments》 CSCD 2024年第2期105-116,共12页
Optical frequency combs,as powerful tools for precision spectroscopy and research into optical frequency standards,have driven continuous progress and significant breakthroughs in applications such as time-frequency t... Optical frequency combs,as powerful tools for precision spectroscopy and research into optical frequency standards,have driven continuous progress and significant breakthroughs in applications such as time-frequency transfer,measurement of fundamental physical constants,and high-precision ranging,achieving a series of milestone results in ground-based environments.With the continuous maturation and evolution of femtosecond lasers and related technologies,optical frequency combs are moving from ground-based applications to astronomical and space-based applications,playing an increasingly important role in atomic clocks,exoplanet observations,gravitational wave measurements,and other areas.This paper,focusing on astronomical and space-based applications,reviews research progress on astronomical frequency combs,optical clock time-frequency networks,gravitational waves,dark matter measurement,dual-comb large-scale absolute ranging,and high-resolution atmospheric spectroscopy.With enhanced performance and their gradual application in the field of space-based research,optical frequency combs will undoubtedly provide more powerful support for astronomical science and cosmic exploration in the future. 展开更多
关键词 Optical frequency comb Astronomical comb Optical clock-based time and frequency network Gravitational waves and dark matter Dual-comb ranging
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Combing the Globe
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作者 DING WENLEI 《Beijing Review》 2010年第4期32-33,共2页
China’s top comb maker aims to sell its high-end hand-crafted products to overseas customers while improving its brand image For some, woodcarving and small carpentry work are hobbies. But for Tan Chuanhua and his ... China’s top comb maker aims to sell its high-end hand-crafted products to overseas customers while improving its brand image For some, woodcarving and small carpentry work are hobbies. But for Tan Chuanhua and his Carpenter Tan comb brand, the woodworking craft has become a deep-rooted moneymaker. The Chongqing-based handcraft wood comb maker raised HK$140 million ($18 mil- 展开更多
关键词 combing the Globe
原文传递
Wavelength switchable mode-locked fiber laser with a few-mode fiber filter
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作者 白少康 向昱锦 张祖兴 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期311-315,共5页
We have proposed and constructed a few-mode fiber(FMF)-based comb filter realized by dislocation splicing a fewmode long-period fiber grating(FM-LPFG) with a single-mode fiber(SMF). From an all-fiber laser with a FMF-... We have proposed and constructed a few-mode fiber(FMF)-based comb filter realized by dislocation splicing a fewmode long-period fiber grating(FM-LPFG) with a single-mode fiber(SMF). From an all-fiber laser with a FMF-based comb filter, the generation of switchable single-, dual-, triple-, and quadruple-wavelength continuous light has been achieved.Moreover, wavelength switchable mode-locked pulses have been obtained with the increased pump power. In the experiment, the output wavelength of the mode-locked fiber laser was changed from 1567.72 nm to 1571.04 nm, while the signal-to-noise(SNR) ratio was maintained above 61 d B. The switchable multiwavelength continuous wave(CW) and mode-locked all-fiber lasers have potentially important applications for fiber sensing, wavelength-division multiplexing(WDM) and signal processing. 展开更多
关键词 few-mode fiber mode-locked pulses few-mode long-period fiber comb filter
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SM9中高次幂运算的快速实现方法
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作者 王江涛 樊荣 黄哲 《计算机工程》 CAS CSCD 北大核心 2023年第9期118-124,136,共8页
国密SM9算法是基于双线性对的标识密码算法,其运行过程需进行多次十二次扩域的高次幂运算,其计算性能对SM9算法体制的应用至关重要。SM9签名运算中的高次幂可以预存点,在运算过程中通过查表减少运算时间。由于验签运算中高次幂的底数不... 国密SM9算法是基于双线性对的标识密码算法,其运行过程需进行多次十二次扩域的高次幂运算,其计算性能对SM9算法体制的应用至关重要。SM9签名运算中的高次幂可以预存点,在运算过程中通过查表减少运算时间。由于验签运算中高次幂的底数不确定,无法通过查表进行运算,因此分别使用Comb固定基和NAF算法在算法模型上降低高次幂中十二次扩域乘法运算量。为提高十二次扩域乘法的计算效率,根据R-ate对的特殊性质提出基于分圆子群的快速平方算法,降低扩域乘法所需的基域运算开销,并将其应用于高次幂的运算中。硬件架构创新性地采用基于自定义RISC指令集的ASIP微码控制方式实现,该架构的灵活性有利于在有限的硬件资源下实现复杂的SM9算法逻辑,其中可修改的指令集可以更好地与底层硬件适配。在Xilinx Artix-7系列的FPGA平台上的实验结果表明,在167 MHz的时钟频率条件下,不增加额外的硬件资源开销,该方法完成一次SM9签名的时间仅为0.244 ms。 展开更多
关键词 SM9算法 高次幂 R-ate对 分圆子群 Comb固定基 NAF算法
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Phase-coherence dynamics of frequency-comb emission via high-order harmonic generation in few-cycle pulse trains
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作者 梁畅通 张晶晶 李鹏程 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期205-211,共7页
Frequency-comb emission via high-order harmonic generation(HHG)provides an alternative method for the coherent vacuum ultraviolet(VUV)and extreme ultraviolet(XUV)radiation at ultrahigh repetition rates.In particular,t... Frequency-comb emission via high-order harmonic generation(HHG)provides an alternative method for the coherent vacuum ultraviolet(VUV)and extreme ultraviolet(XUV)radiation at ultrahigh repetition rates.In particular,the temporal and spectral features of the HHG were shown to carry profound insight into frequency-comb emission dynamics.Here we present an ab initio investigation of the temporal and spectral coherence of the frequency comb emitted in HHG of He atom driven by few-cycle pulse trains.We find that the emission of frequency combs features a destructive and constructive coherences caused by the phase interference of HHG,leading to suppression and enhancement of frequency-comb emission.The results reveal intriguing and substantially different nonlinear optical response behaviors for frequency-comb emission via HHG.The dynamical origin of frequency-comb emission is clarified by analyzing the phase coherence in HHG processes in detail.Our results provide fresh insight into the experimental realization of selective enhancement of frequency comb in the VUV–XUV regimes. 展开更多
关键词 high-order harmonic generation frequency comb time-dependent Schro¨dinger equation intense laser field systems
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Two New Species of Fire-Bellied Newts (Caudata, Salamandridae, Cynops) from Southeastern China
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作者 Zhitong LYU Shuo QI +2 位作者 Siyu ZHANG Keyuan DAI Yingyong WANG 《Asian Herpetological Research》 SCIE CSCD 2023年第1期41-53,I0003,共14页
The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdon... The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdong and Cynops maguae sp.nov.distributed in eastern Jiangxi.The two new species can be distinctly distinguished from their congeners by the independent phylogenetic placements and a combination of morphological characteristics.The discovery of these two new species in the Southeast Chinese Hilly Area,where half of congeners occur,increases the known diversity of Cynops,and indicates unresolved relationships among the species in southeastern China.Further discussions on the taxonomic status of Cynops cyanurus are also provided. 展开更多
关键词 Cynops jiaoren sp.nov. Cynops maguae sp.nov. Cynops yunnanensis comb.nov. Southeast Chinese Hilly Area taxonomy
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Rare case of lupus enteritis presenting as colorectum involvement:A case report and review of literature
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作者 Hui Gan Fei Wang +1 位作者 Yuan Gan Li Wen 《World Journal of Clinical Cases》 SCIE 2023年第34期8176-8183,共8页
BACKGROUND Systemic lupus erythematosus(SLE)is a multisystem autoimmune disease that can affect the gastrointestinal tract.Most cases of lupus enteritis(LE)involve the small intestine,while the involvement of the whol... BACKGROUND Systemic lupus erythematosus(SLE)is a multisystem autoimmune disease that can affect the gastrointestinal tract.Most cases of lupus enteritis(LE)involve the small intestine,while the involvement of the whole colon and rectum without the small intestine being affected is extremely rare.CASE SUMMARY A 35-year-old woman was diagnosed with colorectal LE after initially presenting with intermittent abdominal pain and vomiting for two months.She had a regular medication history for five years following the diagnosis of SLE but had been irregular in taking medications,which may have contributed to the onset of LE and led to her current hospital admission.According to the 2019 Classification criteria for SLE of the European League Against Rheumatism/American College of Rheumatology,this case scored 14.Additionally,abdominal computed tomography revealed significant wall edema of the colon and rectum,ischemia and hyperemia of the ascending colon intestinal wall,mesenteric vessel engorgement,increased mesangial fat attenuation,ascites,and bilateral ureter-hydronephrosis,all indicative of colon and rectum LE.Laboratory tests also showed lower levels of complement C3 and C4,with an antinuclear antibody titer of 1:100.Overall,it was clear that this case involved the colon and rectum without affecting the small intestine,representing a rare manifestation of SLE.The patient received treatment with 10 mg of methylprednisolone sodium succinate,100 mL of 0.9%sodium chloride,hydroxychloroquine(100 mg),and nutrition support.After one week of methylprednisolone and hydroxychloroquine therapy,her SLE symptoms and disease activity improved significantly.CONCLUSION Although colorectal LE without small intestine involvement is very rare,early diagnosis and excellent management with corticosteroids prevented the need for surgical intervention.Physicians should be aware of colorectal LE without small intestine involvement as a manifestation of lupus flare. 展开更多
关键词 Lupus enteritis Systemic lupus erythematosus Colon and rectum Target sign Comb sign Methylprednisolone and hydroxychloroquine Case report
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Comb-Based Filter Design Using Sharpening Technique and Certain Palindromic Polynomial
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作者 Gordana Jovanovic Dolecek 《Journal of Applied Mathematics and Physics》 2023年第11期3773-3781,共9页
This paper presents a novel approach to improve aliasing rejection in comb-based decimation filters. The method is established on certain palindromic polynomials with all zeros on the unit circle and the sharpening te... This paper presents a novel approach to improve aliasing rejection in comb-based decimation filters. The method is established on certain palindromic polynomials with all zeros on the unit circle and the sharpening technique. As a result, aliasing rejection and the passband characteristic are improved. The method is illustrated with various examples and compared with the methods from the literature. . 展开更多
关键词 Comb Filter ALIASING Passband Droop Palindromic Polynomial SHARPENING
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基于Frobenius映射的快速标量乘算法 被引量:2
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作者 殷新春 侯红祥 谢立 《计算机研究与发展》 EI CSCD 北大核心 2008年第9期1561-1566,共6页
标量乘法的效率决定着椭圆曲线密码体制的性能,而Koblitz曲线上的快速标量乘算法是标量乘法研究的重要课题,在标量k的TNAF约简基础上,给出了一种基于Frobenius映射的上层运算:Comb算法.在预计算阶段,该算法利用Frobenius映射对宽... 标量乘法的效率决定着椭圆曲线密码体制的性能,而Koblitz曲线上的快速标量乘算法是标量乘法研究的重要课题,在标量k的TNAF约简基础上,给出了一种基于Frobenius映射的上层运算:Comb算法.在预计算阶段,该算法利用Frobenius映射对宽度为r的序列计算其对应椭圆曲线上的点,从而建立预计算表,在累加赋值阶段结合约简后的TNAF(k)和预计算表来提高效率.Comb算法基于高效的Frobenius映射无须进行倍点运算,经过Comb矩阵的组合,其所需点加量是传统算法的1/5~1/4,当行数r任意时,其效率在任意坐标下比传统Comb算法提高至少67%. 展开更多
关键词 椭圆曲线密码体制 标量乘法 KOBLITZ曲线 Frobenius映射 Comb算法
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桩锚复合土钉基于测斜曲线的主动土压力反演分析 被引量:3
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作者 李峰 郭院成 +1 位作者 刘建伟 何东林 《信阳师范学院学报(自然科学版)》 CAS 北大核心 2007年第4期436-438,共3页
针对桩锚与土钉组合支护进行协同工作设计计算中土压力分配的困难,根据基坑工程中常规的桩锚土钉组合支护测斜监测数据,推导了一种能够估算组合支护土压力分配的方法,使深基坑工程能够根据具体测斜变形量估算桩锚土钉组合支护体系的有... 针对桩锚与土钉组合支护进行协同工作设计计算中土压力分配的困难,根据基坑工程中常规的桩锚土钉组合支护测斜监测数据,推导了一种能够估算组合支护土压力分配的方法,使深基坑工程能够根据具体测斜变形量估算桩锚土钉组合支护体系的有效发挥水平,使组合支护设计更加趋于合理. 展开更多
关键词 主动土压力 桩锚 土钉墙 测斜曲线 反演
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A Discovery of Anomozamites with Reproductive Organs 被引量:2
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作者 郑少林 张立军 巩恩普 《Acta Botanica Sinica》 CSCD 2003年第6期667-672,共6页
Anomozamites haifanggouensis (Kimura et al.) Zheng et Zhang comb. nov. is a characteristic Bennettitalean plant in Middle Jurassic flora. Only one specimen was collected from Haifanggou Formation (Middle Jurassic) in ... Anomozamites haifanggouensis (Kimura et al.) Zheng et Zhang comb. nov. is a characteristic Bennettitalean plant in Middle Jurassic flora. Only one specimen was collected from Haifanggou Formation (Middle Jurassic) in Daohugou village, Shantou town, Ningcheng County, Nei Mongol Autonomous Region, China. The stem of plant is slender and repeatedly branches as a dichasial system with a fertile shoot in the fork, forming equal and widely divergent branches, on the branches born with the fronds of Anomozamites type. Its reproductive organs consists of some microsporophylls and a few of the bracteoid small leaves (or receptacular leaves). Some scattered bracteoid leaves and microsporophylls were formerly considered by Pan as dicots. Since then, they were proposed to be a non-committal genus Pankuangia and described them as P. haifanggouensis by Kimura et al. In this study, we discover that these bracteoid small leaves and microsporophylls should be of Anomozamites. This discovery provides strong evidence for the 'Pankuangia' determination of the taxonomical position. 展开更多
关键词 Anomozamites haifanggouensis (Kimura et al.) comb. nov. reproductive organ Nei Mongol Middle Jurassic Haifanggou Formation
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一种改进的Fixed-base Comb安全快速算法 被引量:1
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作者 殷新春 王圆圆 侯红祥 《小型微型计算机系统》 CSCD 北大核心 2007年第6期1080-1083,共4页
本文从分析椭圆曲线上Fixed-baseComb算法出发,根据其特点,利用牺牲乘法操作以降低求逆操作的方法,分别用2kP、2P+Q的快速算法对Fixed-baseComb算法的预计算阶段和赋值阶段进行改进,极大地提高了计算效率:在素数域上预计算阶段提高70%~... 本文从分析椭圆曲线上Fixed-baseComb算法出发,根据其特点,利用牺牲乘法操作以降低求逆操作的方法,分别用2kP、2P+Q的快速算法对Fixed-baseComb算法的预计算阶段和赋值阶段进行改进,极大地提高了计算效率:在素数域上预计算阶段提高70%~80%,而赋值阶段提高38%~43%,同时,改进算法通过对k的预处理,使得算法能够抵抗边际信道攻击. 展开更多
关键词 ECC 标量乘法 底层域运算 直接计算 Fixed—base Comb算法 边际信道攻击
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血清SCML2在胃肠胰神经内分泌肿瘤中的表达及临床意义 被引量:1
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作者 李梅 马剑波 +3 位作者 吴芸妤 纪易斐 肖明兵 钱坤艳 《临床肿瘤学杂志》 CAS 北大核心 2020年第3期251-256,共6页
目的探讨血清SCML2蛋白在胃肠胰神经内分泌肿瘤(GEP-NENs)中的表达及临床意义。方法收集南通大学附属医院2009年1月至2014年1月GEP-NENs组织和血清标本64例,另外收集同时期胃、肠、胰腺癌(均为腺癌)和胃肠息肉手术患者各30例组织和血清... 目的探讨血清SCML2蛋白在胃肠胰神经内分泌肿瘤(GEP-NENs)中的表达及临床意义。方法收集南通大学附属医院2009年1月至2014年1月GEP-NENs组织和血清标本64例,另外收集同时期胃、肠、胰腺癌(均为腺癌)和胃肠息肉手术患者各30例组织和血清标本。采用TRFIA法检测血清SCML2水平,采用免疫组化法检测组织中SCML2蛋白表达。分析血清SCML2表达与GEP-NENs临床病理特征及预后的关系。结果GEP-NENs患者血清SCML2蛋白表达量[(62.50±34.0)ng/ml]明显高于腺癌患者[(24.89±15.32)ng/ml]、胃肠息肉患者[(21.83±16.49)ng/ml],差异具有统计学意义(P<0.05);且血清SCML2蛋白表达与病理类型、病理分级、浸润深度、TNM分期有关(P<0.05)。GEP-NENs患者血清SCML2水平与血清CgA水平(r=0.649,P<0.05)、组织SCML2蛋白表达(r=0.814,P<0.05)呈正相关。ROC曲线分析,血清SCML2诊断GEP-NENs的效能高于血清CgA[0.871(95%CI:0.812~0.930)vs.0.714(95%CI:0.624~0.804)]。GEP-NENs患者随访时间为2~125个月,中位生存时间(OS)为48.0个月(37.6~58.4个月),其中血清SCML2低表达患者中位OS为89.0个月(29.2~148.8个月),高于血清SCML2高表达患者中位OS为42.0个月(28.2~55.9个月),差异有统计学差异(χ^2=9.442,P=0.002)。结论血清SCML2在GEP-NENs患者中的表达量明显升高,与病理类型、病理分级、浸润深度、TNM分期、预后不良有关。 展开更多
关键词 胃肠胰神经内分泌肿瘤(GEP-NENs) SEX COMB on midleg like-2(SCML2) 时间分辨荧光免疫检测法(TRFIA) 嗜铬粒素A(CgA) 预后
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