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Effect of Addition of Er-TiB_(2)Dual-Phase Nanoparticles on Strength-Ductility of Al-Mn-Mg-Sc-Zr Alloy Prepared by Laser Powder Bed Fusion
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作者 Li Suli Zhang Yanze +5 位作者 Yang Mengjia Zhang Longbo Xie Qidong Yang Laixia MaoFeng Chen Zhen 《稀有金属材料与工程》 北大核心 2026年第1期9-17,共9页
A dual-phase synergistic enhancement method was adopted to strengthen the Al-Mn-Mg-Sc-Zr alloy fabricated by laser powder bed fusion(LPBF)by leveraging the unique advantages of Er and TiB_(2).Spherical powders of 0.5w... A dual-phase synergistic enhancement method was adopted to strengthen the Al-Mn-Mg-Sc-Zr alloy fabricated by laser powder bed fusion(LPBF)by leveraging the unique advantages of Er and TiB_(2).Spherical powders of 0.5wt%Er-1wt%TiB_(2)/Al-Mn-Mg-Sc-Zr nanocomposite were prepared using vacuum homogenization technique,and the density of samples prepared through the LPBF process reached 99.8%.The strengthening and toughening mechanisms of Er-TiB_(2)were investigated.The results show that Al_(3)Er diffraction peaks are detected by X-ray diffraction analysis,and texture strength decreases according to electron backscatter diffraction results.The added Er and TiB_(2)nano-reinforcing phases act as heterogeneous nucleation sites during the LPBF forming process,hindering grain growth and effectively refining the grains.After incorporating the Er-TiB_(2)dual-phase nano-reinforcing phases,the tensile strength and elongation at break of the LPBF-deposited samples reach 550 MPa and 18.7%,which are 13.4%and 26.4%higher than those of the matrix material,respectively. 展开更多
关键词 Al-Mn-Mg-Sc-Zr alloy laser powder bed fusion nano-reinforcing phase synergistic enhancement
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Sonazoid-contrast-enhanced ultrasound for the histological diagnosis of hepatocellular carcinoma
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作者 Ruo-Bing Liu Jun-Yi Xin +1 位作者 Zhe Huang Kai-Yan Li 《World Journal of Gastrointestinal Oncology》 2026年第1期122-134,共13页
BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter... BACKGROUND The treatment technology of liver cancer is progressing.In addition to traditional surgical resection,combined therapies of immunotherapy based on immune checkpoint inhibitors,chemotherapy,and transcatheter arterial chemoembolization for hepatocellular carcinoma are more and more widely used.Accurate preoperative diagnosis of liver cancer will provide important information for comprehensive treatment and prognosis evaluation of liver cancer.Sonazoidcontrast-enhanced ultrasound is not only helpful for the qualitative diagnosis of liver lesions,but also has great potential in the diagnosis of histological differentiation of liver cancer.AIM To assess the differentiation of hepatocellular carcinoma(HCC)by utilizing the parameters and imaging features of Sonazoid-contrast-enhanced ultrasound(CEUS).METHODS A retrospective analysis was conducted on the CEUS data of 239 lesions through case-control study.These patients received Sonazoid-CEUS within one week before surgery and were confirmed as HCC by postoperative pathology.Within the cases,patients were further categorized into well-differentiated and poorlydifferentiated group.Time-intensity curves of the region of interest in both arterial and Kupffer phases were generated,allowing for the acquisition of quantitative parameters to assess the diagnostic efficacy in distinguishing lesions between these two groups and determining an appropriate cut-off value.RESULTS Univariate analysis showed that the absolute value of enhancement intensity(EIAV),intensity ratio(IR)and intensity difference(ID)in Kupffer phase were statistically different between the groups with different degree(P=0.015,P=0.000,P=0.000).The sensitivity and specificity were 40.2%,82.4%,80.4% and 78.1%,86.9% and 74.5%,respectively,for differentiating HCC lesions with EIAV≥56.384 dB,IR≥1.215 and ID≥9.184 dB.The area under the receiver operating characteristic curve were 0.590,0.877,0.815.There was no significant difference in the parameters of arterial phase,including peak time,initial growth time,rise time and the absolute value of peak intensity of lesions between the two groups(P>0.05).Multivariate analysis showed that the level of alphafetoprotein(AFP)and IR were risk factors for poor differentiation(P=0.001).CONCLUSION Among the parameters of Sonazoid-CEUS,IR in Kupffer phase exhibits superior diagnostic efficacy with high sensitivity and specificity in the diagnose of pathological differentiation of HCC.Combined with preoperative AFP level,a more accurate diagnosis will be obtained.Compared with portal vein phase,Kupffer phase showed the ability to identify HCC lesions more sensitive.These findings hold significant guiding implications and reference value for clinical practice. 展开更多
关键词 Contrast-enhanced ultrasound Hepatocellular carcinoma Quantitative parameters Kupffer phase Pathological differentiation
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Moisture-Resistant Scalable Ambient-Air Crystallization of Perovskite Films via Self-Buffered Molecular Migration Strategy
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作者 Mei Yang Weidong Zhu +9 位作者 Laijun Liang Wenming Chai Xiaomeng Wu Zeyang Ren Long Zhou Dazheng Chen He Xi Chunfu Zhang Jincheng Zhang Yue Hao 《Nano-Micro Letters》 2026年第2期421-438,共18页
Ambient-air,moisture-assisted annealing is widely used in fabricating perovskite solar cells(PSCs).However,the inherent sensitivity of perovskite intermediate-phase to moisture—due to fast and spontaneous intermolecu... Ambient-air,moisture-assisted annealing is widely used in fabricating perovskite solar cells(PSCs).However,the inherent sensitivity of perovskite intermediate-phase to moisture—due to fast and spontaneous intermolecular exchange reaction—requires strict control of ambient humidity and immediate thermal annealing treatment,raising manufacturing costs and causing fast nucleation of perovskite films.We report herein a self-buffered molecular migration strategy to slow down the intermolecular exchange reaction by introducing a n-butylammonium bromide shielding layer,which limits moisture diffusion into intermediate-phase film.This further endows the notably wide nucleation time and humidity windows for perovskite crystallization in ambient air.Consequently,the optimized 1.68 e V-bandgap n-i-p structured PSC reaches a record-high reverse-scan(RS)PCE of 22.09%.Furthermore,the versatility and applicability of as-proposed self-buffered molecular migration strategy are certified by employing various shielding materials and 1.53 eV-/1.77 eV-bandgap perovskite materials.The n-i-p structured PSCs based on 1.53 eV-and 1.77 eV-bandgap perovskite films achieve outstanding RS PCEs of 25.23%and 19.09%,respectively,both of which are beyond of the state-of-the-art ambient-air processed PSCs. 展开更多
关键词 Perovskite solar cell Ambient-air annealing Intermediate phase Intermolecular exchange High-humidity crystallization
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Lattice Anchoring Stabilizesα-FAPbI_(3) Perovskite for High-Performance X-Ray Detectors
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作者 Yu-Hua Huang Su-Yan Zou +5 位作者 Cong-Yi Sheng Yu-Chuang Fang Xu-Dong Wang Wei Wei Wen-Guang Li Dai-Bin Kuang 《Nano-Micro Letters》 2026年第1期337-354,共18页
Formamidinium lead iodide(FAPbI_(3))perovskite exhibits an impressive X-ray absorption coefficient and a large carrier mobility-lifetime product(μτ),making it as a highly promising candidate for X-ray detection appl... Formamidinium lead iodide(FAPbI_(3))perovskite exhibits an impressive X-ray absorption coefficient and a large carrier mobility-lifetime product(μτ),making it as a highly promising candidate for X-ray detection application.However,the presence of larger FA^(+)cation induces to an expansion of the Pb-I octahedral framework,which unfortunately affects both the stability and charge carrier mobility of the corresponding devices.To address this challenge,we develop a novel low-dimensional(HtrzT)PbI_(3) perovskite featuring a conjugated organic cation(1H-1,2,4-Triazole-3-thiol,HtrzT^(+))which matches well with theα-FAPbI_(3) lattices in two-dimensional plane.Benefiting from the matched lattice between(HtrzT)PbI_(3) andα-FAPbI_(3),the anchored lattice enhances the Pb-I bond strength and effectively mitigates the inherent tensile strain of theα-FAPbI_(3) crystal lattice.The X-ray detector based on(HtrzT)PbI_(3)(1.0)/FAPbI_(3) device achieves a remarkable sensitivity up to 1.83×10^(5)μC Gy_(air)^(−1) cm^(−2),along with a low detection limit of 27.6 nGy_(air) s^(−1),attributed to the release of residual stress,and the enhancement in carrier mobility-lifetime product.Furthermore,the detector exhibits outstanding stability under X-ray irradiation with tolerating doses equivalent to nearly 1.17×10^(6) chest imaging doses. 展开更多
关键词 α-FAPbI_(3)perovskite Conjugated organic cation Lattice anchoring Phase stability X-ray detectors
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Preparation of Flame Retardant Containing Phosphorus-nitrogen-boron and Its Application in Polyethylene
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作者 CONG Mengchen LU Shangkai +3 位作者 FANG Jin LIU Junbang AI Lianghui LIU Ping 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期275-284,共10页
MPHPB was prepared from melamine,phenylphosphonic acid and boric acid,and its flame retardant effect in PE was investigated.Compared to the intermediate product(melamine phenyl hypophosphite(MPHP)),the residual char i... MPHPB was prepared from melamine,phenylphosphonic acid and boric acid,and its flame retardant effect in PE was investigated.Compared to the intermediate product(melamine phenyl hypophosphite(MPHP)),the residual char increased from 17.9% of MPHP to 41.2% of MPHPB at 800℃.The limiting oxygen index(LOI)of PE/20%MPHPB is 23.6%,which reaches V-0 rating.After the addition of 20%MPHPB,the total heat release(THR),peak heat release rate(pK-HRR),and average effective thermal combustion rates(av-EHC)of PE decreased.Additionally,characterizations including the pyrolysis gas chromatography-mass spectrometry(Py-GC-MS),scanning electron microscopy(SEM),raman spectroscopy test(LRS)and fourier transform infrared(FT-IR)were taken to investigate the flame retardant mechanism,and the results show that MPHPB plays roles in both gas and condensed phases. 展开更多
关键词 polythene phosphorus-nitrogen-boron compound flame retardant flame retardant mecha‐nism gas and condensed phases flame retardant
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Spinal cord injury and inflammatory mediators:Role in“fire barrier”formation and potential for neural regeneration
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作者 Mi Zhou Zhengyu Xu +2 位作者 Hao Zhong Guangzhi Ning Shiqing Feng 《Neural Regeneration Research》 2026年第3期923-937,共15页
Traumatic spinal cord injury result in considerable and lasting functional impairments,triggering complex inflammatory and pathological events.Spinal cord scars,often metaphorically referred to as“fire barriers,”aim... Traumatic spinal cord injury result in considerable and lasting functional impairments,triggering complex inflammatory and pathological events.Spinal cord scars,often metaphorically referred to as“fire barriers,”aim to control the spread of neuroinflammation during the acute phase but later hinder axon regeneration in later stages.Recent studies have enhanced our understanding of immunomodulation,revealing that injury-associated inflammation involves various cell types and molecules with positive and negative effects.This review employs bibliometric analysis to examine the literature on inflammatory mediators in spinal cord injury,highlighting recent research and providing a comprehensive overview of the current state of research and the latest advances in studies on neuroinflammation related to spinal cord injury.We summarize the immune and inflammatory responses at different stages of spinal cord injury,offering crucial insights for future research.Additionally,we review repair strategies based on inflammatory mediators for the injured spinal cord.Finally,this review discusses the current status and future directions of translational research focused on immune-targeting strategies,including pharmaceuticals,biomedical engineering,and gene therapy.The development of a combined,precise,and multitemporal strategy for the repair of injured spinal cords represents a promising direction for future research. 展开更多
关键词 axon regeneration bibliometric analysis central nervous system chronic phase conditioning lesion paradigm glia scar immunomodulatory pharmaceutics inflammatory mediator NEUROINFLAMMATION spinal cord injury zebrafish
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Multi-spacecraft Intelligent Orbit Phasing Control Considering Collision Avoidance 被引量:1
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作者 LI Jian ZHANG Gang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第4期379-388,共10页
This paper proposes an intelligent low-thrust orbit phasing control method for multiple spacecraft by simultaneously considering fuel optimization and collision avoidance. Firstly,the minimum-fuel orbit phasing contro... This paper proposes an intelligent low-thrust orbit phasing control method for multiple spacecraft by simultaneously considering fuel optimization and collision avoidance. Firstly,the minimum-fuel orbit phasing control database is generated by the indirect method associated with the homotopy technique. Then,a deep network representing the minimum-fuel solution is trained. To avoid collision for multiple spacecraft,an artificial potential function is introduced in the collision-avoidance controller. Finally,an intelligent orbit phasing control method by combining the minimum-fuel neural network controller and the collision-avoidance controller is proposed. Numerical results show that the proposed intelligent orbit phasing control is valid for the multi-satellite constellation initialization without collision. 展开更多
关键词 orbit phasing control low thrust deep neural networks collision avoidance
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Enhancement of MAD/MIR phasing at low resolution and a new procedure for automatic phase extension
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作者 Pu Han Yuan-Xin Gu +1 位作者 Wei Ding Hai-Fu Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期389-395,共7页
To achieve de novo protein structure determination of challenging cases, multi-wavelength anomalous diffraction(MAD) and multiple isomorphous replacement(MIR) phasing can be powerful tools to obtain low-resolution ini... To achieve de novo protein structure determination of challenging cases, multi-wavelength anomalous diffraction(MAD) and multiple isomorphous replacement(MIR) phasing can be powerful tools to obtain low-resolution initial phases from heavy-atom derivative datasets, then phase extension is needed against high-resolution data to obtain accurate structures.In this context, we propose a direct-methods procedure here that could improve the initial low-resolution MAD/MIR phase quality.And accordingly, an automated process for extending initial phases to high resolution is also described.These two procedures are both implanted in the newly released IPCAS pipeline.Three cases are used to perform the test, including one set of 4.17 ? MAD data from a membrane protein and two sets of MAD/MIR data with derivatives truncated down to 6.80 ? and 6.90 ?, respectively.All the results have shown that the initial phases generated from the direct-methods procedure are better than that from the conventional MAD/MIR methods.The automated phase extensions for the latter two cases starting from 6.80 ? to 3.00 ? and 6.90 ? to 2.80 ? are proved to be successful, leading to complete models.This may provide convenient and reliable tools for phase improvement and phase extension in difficult low-resolution tasks. 展开更多
关键词 direct methods MULTI-WAVELENGTH anomalous diffraction(MAD)/multiple isomorphous replacement(MIR) phasing PHASE EXTENSION low-resolution
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SAD phasing by OASIS at different resolutions down to 0.30 nm and below
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作者 姚德强 李鹤 +6 位作者 陈强 古元新 郑朝德 林政炯 范海福 渡邉信久 沙炳东 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期1-9,共9页
Single-wavelength anomalous diffraction (SAD) phasing is increasingly important in solving de novo protein structures. Direct methods have been proved very efficient in SAD phasing. This paper aims at probing the lo... Single-wavelength anomalous diffraction (SAD) phasing is increasingly important in solving de novo protein structures. Direct methods have been proved very efficient in SAD phasing. This paper aims at probing the low-resolution limit of direct-method SAD phasing. Two known proteins TT0570 and Tom70p were used as test samples. Sulfur-SAD data of the protein TT0570 were collected with conventional Cu-Kα source at 0.18 nm resolution. Its truncated subsets respectively at 0.21, 0.30, 0.35 and 0.40 nm resolutions were used in the test. TT0570 Cu-Kα sulfur-SAD data have an expected Bijvoet ratio 〈 |△F| 〉 / 〈 F 〉 ~ 0.55%. In the 0.21 nm case, a single run of OASIS-DM-ARP/wARP led automatically to a model containing 1178 of the total 1206 residues all docked into the sequence. In 0.30 and 0.35 nm cases, SAD phasing by OASIS-DM led to traceable electron density maps. In the 0.40 nm case, SAD phasing by OASIS-DM resulted in a degraded electron density map, which may be difficult to trace but still contains useful secondary-structure information. Test on real 0.33 nm selenium-SAD data of the protein Tom70p showed that even automatic model building was not successful, the combination of manual tracing and direct-method fragment extension was capable of significantly improving the electron-density map. This provides the possibility of effectively improving the manually built model before structure refinement is performed. 展开更多
关键词 OASIS SAD phasing dual-space fragment extension PROTEINS
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Method for Collision Avoidance in Spacecraft Rendezvous Problems with Space Objects in a Phasing Orbit
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作者 Danhe Chen A.A.Baranov +2 位作者 Chuangge Wang M.O.Karatunov N.Yu.Makarov 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第6期977-991,共15页
As the number of space objects(SO)increases,collision avoidance problem in the rendezvous tasks or reconstellation of satellites with SO has been paid more attention,and the dangerous area of a possible collision shou... As the number of space objects(SO)increases,collision avoidance problem in the rendezvous tasks or reconstellation of satellites with SO has been paid more attention,and the dangerous area of a possible collision should be derived.In this paper,a maneuvering method is proposed for avoiding collision with a space debris object in the phasing orbit of the initial optimal solution.Accordingly,based on the plane of eccentricity vector components,relevant dangerous area which is bounded by two parallel lines is formulated.The axises of eccentricity vector system pass through the end of eccentricity vector of phasing orbit in the optimal solution,and orientation of axis depends on the latitude argument where a collision will occur.The dangerous area is represented especially with the graphical dialogue,and it allows to find a compromise between the SO avoiding and the fuel consumption reduction.The proposed method to solve the collision avoidance problem provides simplicity to calculate rendezvous maneuvers,and possibility to avoid collisions from several collisions or from“slow”collisions in a phasing orbit,when the protected spacecraft and the object fly dangerously close to each other for a long period. 展开更多
关键词 SPACECRAFT collision avoidance rendezvous problem space objects phasing orbit
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Haplotype phasing after joint estimation of recombination and linkage disequilibrium in breeding populations
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作者 Luis Gomez-Raya Amanda M Hulse +1 位作者 David Thain Wendy M Rauw 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第1期38-52,共15页
A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from Monte Carlo computer simulations show that the newly developed E.... A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from Monte Carlo computer simulations show that the newly developed E.M. algorithm is accurate if true recombination fraction is 0 even for single families of relatively small sizes. Estimates of recombination fraction and linkage disequilibrium were 0.00 (SD 0.00) and 0.19 (SD 0.03) for simulated recombination fraction and linkage disequilibrium of 0.00 and 0.20, respectively. A genome fragmentation phasing strategy was developed and used for phasing haplotypes in a sire and 36 progeny using the 50 k Illumina BeadChip by: a) estimation of the recombination fraction and LD in consecutive SNPs using family information, b) linkage analyses between fragments, c) phasing of haplotypes in parents and progeny and in following generations. Homozygous SNPs in progeny allowed determination of paternal fragment inheritance, and deduction of SNP sequence information of haplotypes from dams. The strategy also allowed detection of genotyping errors. A total of 613 recombination events were detected after linkage analysis was carried out between fragments. Hot and cold spots were identified at the individual (sire level). SNPs for which the sire and calf were heterozygotes became informative (over 90%) after the phasing of haplotypes. Average of regions of identity between half-sibs when comparing its maternal inherited haplotypes (with at least 20 SNP) in common was 0.11 with a maximum of 0.29 and a minimum of 0.05. A Monte-Carlo simulation of BTA1 with the same linkage disequilibrium structure and genetic linkage as the cattle family yielded a 99.98 and 99.94% of correct phases for informative SNPs in sire and calves, respectively. 展开更多
关键词 BREEDING Haplotype phasing Linkage disequilibrium SNP
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SIR phasing by combination of SOLVE/RESOLVE and dual-space fragment extension involving OASIS
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作者 何尧 古元新 +2 位作者 林政炯 郑朝德 范海福 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期3022-3028,共7页
A new phasing procedure has been proposed for dealing with single isomorphous replacement (SIR) x-ray diffraction data. The procedure combines SOLVE/RESOLVE with the dual-space fragment extension involving OASIS. Tw... A new phasing procedure has been proposed for dealing with single isomorphous replacement (SIR) x-ray diffraction data. The procedure combines SOLVE/RESOLVE with the dual-space fragment extension involving OASIS. Two sets of SIR data at 0.28 nm resolution taken from the protein (R)-phycoerythrin (PDB code: 1LIA) were used in the test. For one of the two SIR data sets, a default run of SOLVE/RESOLVE based on the heavy-atom substructure found by SHLEXD led automatically to an interpretable electron density map. OASIS could not effectively improve the result. For the other set of SIR data, SOLVE/RESOLVE resulted in a fragmented model consisting of 454 of the total 668 residues, in which only 29 residues were docked into the sequence. Based on this model, 7 iteration cycles of OASIS-DM- RESOLVE (build only) yielded automatically a model of 547 residues with 133 residues docked into the sequence. The overall-averaged phase error decreased considerably and the quality of electron density map was improved significantly. Two more cycles of iterative OASIS-DM-RESOLVE were carried out, in which the output phases and figures of merit from DM were merged with that from the original run of SOLVE/RESOLVE before they were passed onto RESOLVE (build only). This led automatically to a model containing 452 residues with 173 docked into the sequence. The resultant electron density map is manually traceable. It is concluded that when results of SOLVE/RESOLVE are not sufficiently satisfactory, the combination of SOLVE/RESOLVE and OASIS-DM-RESOLVE (build only) may significantly improve them. 展开更多
关键词 SIR phasing SOLVE/RESOLVE OASIS dual-space fragment extension for proteins
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Role of phase fluctuation and dephasing in the enhancing continuous variable entanglement of a two-photon coherent beat laser
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作者 Sintayehu Tesfa 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期210-221,共12页
A steady state analysis of the nonclassical features and statistical properties of the cavity radiation of a two- photon coherent beat laser is presented. Results show that the degree of two-mode squeezing, detectable... A steady state analysis of the nonclassical features and statistical properties of the cavity radiation of a two- photon coherent beat laser is presented. Results show that the degree of two-mode squeezing, detectable entanglement and intensity of the cavity radiation can increase with the deviation of the phase fluctuations of the laser employed in preparing the atoms, but decrease with the increasing rate at which the induced coherence superposition decays. Although it is found that varying the phase fluctuations and dephasing can lead to modification in the quantum features and statistical properties of the radiation, it does not alter the similarity in the nature of the degree of entanglement detectable by the criteria following from Duan-Giedke-Cirac Zoller and logarithmic negativity in a perceivable manner. Since the intensity and quantum features can be readily enhanced, this system is expected to be a viable source of a strong robust entangled (squeezed) light under various conditions. Moreover, comparison of the mean number of photon pairs with intensity difference shows that the chance of inciting a two-photon process can be enhanced by changing the rate of dephasing and phase fluctuations. 展开更多
关键词 coherent beat laser phase fluctuations DEphasing ENTANGLEMENT
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Geometric Phases Corrected by Stochastic Dephasing
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作者 MA Xiao-San WANG An-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1179-1181,共3页
We analyze the effect of stochastic dephasing on geometric phases. The result implies that the correction of geometric phases relies on not only the fluctuation of the random variable in the stochastic process, but al... We analyze the effect of stochastic dephasing on geometric phases. The result implies that the correction of geometric phases relies on not only the fluctuation of the random variable in the stochastic process, but also the frequency of the system. 展开更多
关键词 stochastic dephasing geometric phase
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A new measuring technique in detecting of high voltage three phase induction motor for single phasing
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作者 Ali M El-Rifaie Hala M Abdel Mageed 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期6-11,共6页
Open phase in three phase induction motors is a common fault that can occur as a result of a fuse blowing or a pro- tective device failing on one phase of the motor. This paper introduces a new method,which is based o... Open phase in three phase induction motors is a common fault that can occur as a result of a fuse blowing or a pro- tective device failing on one phase of the motor. This paper introduces a new method,which is based on the transient mea- surement and can distinguish the fault of one phase connecting ground. The method has been proved to be in correspondence with the simulation results by Matlab and LabVIEW in practice, The method has merits of simplicity, accuracy and ease of USe. 展开更多
关键词 high voltage induction motor transient protection single phasing detection
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Ce-SAD Phasing of Glucose Isomerase and Thermolysin Using Cu <i>Kα</i>Radiation
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作者 Sibi Narayanan Devadasan Velmurugan 《Crystal Structure Theory and Applications》 2013年第3期93-99,共7页
Current structural genomics projects aim to solve a large number of selected protein structures as fast as possible. High degree of automation and standardization is required at every step of the whole process to spee... Current structural genomics projects aim to solve a large number of selected protein structures as fast as possible. High degree of automation and standardization is required at every step of the whole process to speed up protein structure determination. Phase problem is a bottleneck in macromolecular structure determination and also in model building which is a time-consuming task. The simplest approach to phasing macromolecular crystal structures is the use of a SAD signal. SAD data can be collected using the in-house copper (1.54 A) wavelength source. Data collected using copper wavelength with the incorporation of anomalously scattering heavy metal atoms may serve as a powerful tool for structural biologists to solve novel protein structures as well where synchrotron beam line is not available. A short soak of protein crystals in heavy metal solution or by incorporating heavy atoms into the protein drop while crystallizing the protein (co-crystallization) leads to incorporation of these heavy metal ions into the ordered solvent shell around the protein surface. The present work aims to determine whether cerium ion can be successfully incorporated into the protein crystal through quick-soaking method while maintaining the isomorphism. The study also aims in understanding whether this metal ion can be used for phasing purpose. The intensity data are collected and analyzed for anomalous signal, substructure solution and the binding sites. 展开更多
关键词 Anomalous Scattering SAD phasing CE Glucose ISOMERASE THERMOLYSIN
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Dephasing Measurements in InGaAs/AlInAs Heterostructures: Manifestations of Spin-Orbit and Zeeman Interactions
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作者 Lior H. Tzarfati Rafi Hevroni +5 位作者 Amnon Aharony Ora Entin-Wohlman Michael Karpovski Victor Shelukhin Vladimir Umansky Alexander Palevski 《Journal of Modern Physics》 2017年第1期110-125,共16页
We have measured weak antilocalization effects, universal conductance fluctuations, and Aharonov-Bohm oscillations in the two-dimensional electron gas formed in InGaAs/AlInAs heterostructures. This system possesses st... We have measured weak antilocalization effects, universal conductance fluctuations, and Aharonov-Bohm oscillations in the two-dimensional electron gas formed in InGaAs/AlInAs heterostructures. This system possesses strong spin-orbit coupling and a high Landé factor. Phase-coherence lengths of 2 - 4 μm at 1.5 - 4.2 K are extracted from the magnetoconductance measurements. The analysis of the coherence-sensitive data reveals that the temperature dependence of the decoherence rate complies with the dephasing mechanism originating from electron-electron interactions in all three experiments. Distinct beating patterns superimposed on the Aharonov-Bohm oscillations are observed over a wide range of magnetic fields, up to 0.7 Tesla at the relatively high temperature of 1.5 K. The possibility that these beats are due to the interplay between the Aharonov-Bohm phase and the Berry one, different for electrons of opposite spins in the presence of strong spin-orbit and Zeeman interactions in ring geometries, is carefully investigated. It appears that our data are not explained by this mechanism;rather, a few geometrically-different electronic paths within the ring’s width can account for the oscillations’ modulations. 展开更多
关键词 Mesoscopic Physics DECOHERENCE Aharonov BOHM Spin Orbit Interaction Berry Phase
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Safety Performance Functions for Traffic Signals:Phasing and Geometry
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作者 Shane Turner 《Journal of Civil Engineering and Architecture》 2023年第4期199-213,共15页
A significant proportion of urban crashes,especially serious and fatal crashes,occur at traffic signals.Many of the black-spots in both Australia and New Zealand cities occur at high volume and/or high-speed traffic s... A significant proportion of urban crashes,especially serious and fatal crashes,occur at traffic signals.Many of the black-spots in both Australia and New Zealand cities occur at high volume and/or high-speed traffic signals.Given this,crash reduction studies often focus on the major signalised intersections.However,there is limited information that links the phasing configuration,degree of saturation and overall cycle time to crashes.While a number of analysis tools are available for assessing the efficiency of intersections,there are very few tools that can assist engineers in assessing the safety effects of intersection upgrades and new intersections.Safety performance functions have been developed to help quantify the safety impact of various traffic signal phasing configurations and level of intersection congestion at low and high-speed traffic signals in New Zealand and Australia.Data from 238 signalised intersection sites in Auckland,Wellington,Christchurch,Hamilton,Dunedin and Melbourne was used to develop crash prediction models for key crash-causing movements at traffic signals.Different variables(road features)effect each crash type.The models indicate that the safety of intersections can be improved by longer cycle times and longer lost inter-green times,especially all-red time,using fully protected right turns and by extending the length of right turn bays.The exception is at intersections with lots of pedestrians where shorter cycle times are preferred as pedestrian crashes increase with longer wait times.A number of factors have a negative impact on safety including,free left turns,more approach lanes,intersection arms operating near or over capacity in peak periods and higher speed limits. 展开更多
关键词 Crash/Accident prediction models generalized linear models traffic signal layout and phasing pedestrian safety and safety performance functions
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涡流发生器与翼刀组合对风力机叶片气动性能的影响
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作者 杨瑞 杨涛 +3 位作者 曾学仁 方亮 包广超 田楠 《兰州理工大学学报》 北大核心 2025年第5期54-61,共8页
为了研究涡流发生器(VGs)与翼刀组合对风力机叶片气动性能的影响,以NREL Phase VI风力机叶片为模型,采用CFD方法分别对加装单双VGs、单双翼刀及其组合共8种流动控制方式进行模拟,分析在风速不同时对风力机叶片气动性能的影响.结果表明:... 为了研究涡流发生器(VGs)与翼刀组合对风力机叶片气动性能的影响,以NREL Phase VI风力机叶片为模型,采用CFD方法分别对加装单双VGs、单双翼刀及其组合共8种流动控制方式进行模拟,分析在风速不同时对风力机叶片气动性能的影响.结果表明:单VGs与单翼刀组合、双VGs与单翼刀组合不仅能获得更高的输出扭矩,而且能更有效地抑制叶片弦向和展向的流动分离;单VGs与单翼刀组合、双VGs与单翼刀组合可将两装置的优势相结合,展现出更好的流动控制效果;双VGs与单VGs相比能进一步延缓流动分离. 展开更多
关键词 NREL Phase VI风力机 涡流发生器 翼刀 气动性能
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Pharmacological intervention for chronic phase of spinal cord injury 被引量:1
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作者 Chihiro Tohda 《Neural Regeneration Research》 SCIE CAS 2025年第5期1377-1389,共13页
Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challengin... Spinal cord injury is an intractable traumatic injury. The most common hurdles faced during spinal cord injury are failure of axonal regrowth and reconnection to target sites. These also tend to be the most challenging issues in spinal cord injury. As spinal cord injury progresses to the chronic phase, lost motor and sensory functions are not recovered. Several reasons may be attributed to the failure of recovery from chronic spinal cord injury. These include factors that inhibit axonal growth such as activated astrocytes, chondroitin sulfate proteoglycan, myelin-associated proteins, inflammatory microglia, and fibroblasts that accumulate at lesion sites. Skeletal muscle atrophy due to denervation is another chronic and detrimental spinal cord injury–specific condition. Although several intervention strategies based on multiple outlooks have been attempted for treating spinal cord injury, few approaches have been successful. To treat chronic spinal cord injury, neural cells or tissue substitutes may need to be supplied in the cavity area to enable possible axonal growth. Additionally, stimulating axonal growth activity by extrinsic factors is extremely important and essential for maintaining the remaining host neurons and transplanted neurons. This review focuses on pharmacotherapeutic approaches using small compounds and proteins to enable axonal growth in chronic spinal cord injury. This review presents some of these candidates that have shown promising outcomes in basic research(in vivo animal studies) and clinical trials: AA-NgR(310)ecto-Fc(AXER-204), fasudil, phosphatase and tensin homolog protein antagonist peptide 4, chondroitinase ABC, intracellular sigma peptide,(-)-epigallocatechin gallate, matrine, acteoside, pyrvate kinase M2, diosgenin, granulocyte-colony stimulating factor, and fampridine-sustained release. Although the current situation suggests that drug-based therapies to recover function in chronic spinal cord injury are limited, potential candidates have been identified through basic research, and these candidates may be subjects of clinical studies in the future. Moreover, cocktail therapy comprising drugs with varied underlying mechanisms may be effective in treating the refractory status of chronic spinal cord injury. 展开更多
关键词 axonal growth chronic phase clinical study PHARMACOTHERAPY spinal cord injury
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