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L-Lysinium trifluoroacetate

Zhi Hua Sun, Jian Dong Fan, Guang Hui Zhang, Xin Qiang Wang, Dong Xu
2008 Acta Crystallographica Section E  
Key indicators: single-crystal X-ray study; T = 293 K; mean (C-C) = 0.005 Å; disorder in main residue; R factor = 0.045; wR factor = 0.123; data-to-parameter ratio = 7.9.
doi:10.1107/s1600536807068791 pmid:21201423 pmcid:PMC2960259 fatcat:ai3pmhsdubdgvgk3spsciyxsrm

Swerving Orientation of Spin-Stabilized Projectile for Fixed-Cant Canard Control Input

Xu-dong Liu, Dong-guang Li, Qiang Shen
2015 Mathematical Problems in Engineering  
Due to the large launch overload and high spin rate of spin-stabilized projectile, no attitude sensor is adopted in square crossing fixed-cant canard concept, which causes the lack of existing projectile linear theory for the close form solution of swerving motion. This work focuses on swerving orientation prediction with the restricted conditions. By importing the mathematical models of canard force and moment into the projectile angular motion equations, trim angle induced by canard control
more » ... rce is extracted as the analytical solution of angle of attack increment (AOAI). On this basis, analytical orientations of trajectory angular rate increment and swerving increment are obtained via the frozen coefficient method. A series of simulations under different conditions were implemented to validate the expressions in this effort. Results state that increment orientation of swerving motion can be predicted with available trajectory parameters. The analytical orientations indicate trim value of numerical orientations. Deviations between analytical and numerical orientations relate to initial launch angles and control start time, both lower initial launch angle, and the start time which is closer to the end of flight decreases the deviation convergence time.
doi:10.1155/2015/173571 fatcat:a2z2conyr5cfpocw2w5nc7mb2m

Novel Hydrogen Hydrate Structures under Pressure

Guang-Rui Qian, Andriy O. Lyakhov, Qiang Zhu, Artem R. Oganov, Xiao Dong
2014 Scientific Reports  
Gas hydrates are systems of prime importance. In particular, hydrogen hydrates are potential materials of icy satellites and comets, and may be used for hydrogen storage. We explore the H 2 O-H 2 system at pressures in the range 0-100 GPa with ab initio variable-composition evolutionary simulations. According to our calculation and previous experiments, the H 2 O-H 2 system undergoes a series of transformations with pressure, and adopts the known open-network clathrate structures (sII, C 0 ),
more » ... nse "filled ice" structures (C 1 , C 2 ) and two novel hydrate phases. One of these is based on the hexagonal ice framework and has the same H 2 O5H 2 ratio (251) as the C 0 phase at low pressures and similar enthalpy (we name this phase Ih-C 0 ). The other newly predicted hydrate phase has a 152 H 2 O5H 2 ratio and structure based on cubic ice. This phase (which we name C 3 ) is predicted to be thermodynamically stable above 38 GPa when including van der Waals interactions and zero-point vibrational energy, and explains previously mysterious experimental X-ray diffraction and Raman measurements. This is the hydrogen-richest hydrate and this phase has a remarkable gravimetric density (18 wt.%) of easily extractable hydrogen.
doi:10.1038/srep05606 pmid:25001502 pmcid:PMC4085642 fatcat:36oo4xrxxrabjio4cfvdhirzla

Non-equilibrium diffusion characteristics of the particles system and its application

Jian-Qiang Dong, Chun-Guang Li, Peng Wang
2022 figshare.com  
In this paper, we discuss a possible generalization of the social influences of the Langevin equation. Using a functional method of the Kramers–Moyal expansion coefficients, we prove a simple rule for the corresponding Fokker-Planck equation for a generalized one-dimensional system driven by associated Gaussian noise. We propose here a generalization of the nonequilibrium behavior of the probability density and probability currents induced by different combinations of parameters. In addition,
more » ... is interesting to find that the probability of current transport reversal can be obtained by varying the combination of parameters, but the amplitude of the negative and positive currents is controlled by adjusting the interaction coefficient and the intensity factor of the outfield, respectively.
doi:10.6084/m9.figshare.21184387.v1 fatcat:viluycafyrakbi3yixdthp34iy

Target alignment in the Shen-Guang II Upgrade laser facility

Lei Ren, Ping Shao, Dongfeng Zhao, Yang Zhou, Zhijian Cai, Neng Hua, Zhaoyang Jiao, Lan Xia, Zhanfeng Qiao, Rong Wu, Lailin Ji, Dong Liu (+7 others)
2018 High Power Laser Science and Engineering  
The Shen-Guang II Upgrade (SG-II-U) laser facility consists of eight high-power nanosecond laser beams and one short-pulse picosecond petawatt laser.  ...  Target alignment in the Shen-Guang II Upgrade laser facility positioner.  ...  Introduction The Shen-Guang series of laser facilities were constructed to generate fusion ignition and gain in the laboratory [1] [2] [3] [4] .  ... 
doi:10.1017/hpl.2018.4 fatcat:fotrt6uhtjb55pu3k6c4le7v54

Numerical simulation of effect of pump distribution on spherical aberration of end-pumped laser

Yao Qiang-Qiang, Wang Qi-Han, Feng Chi, Chen Si, Jin Guang-Yong, Dong Yuan
2018 Wuli xuebao  
In order to study the spherical aberration of thermal lens when the laser crystal is pumped with the pump light distributed differently and the pump light under the end-pumping condition, in this paper we establish a single-ended pump and constant temperature thermal model to analyze the working characteristics of the Nd:YVO4 crystal. The steady state heat conduction equation and Zernike polynomials are solved, and the relationship between thermal spherical aberration and distribution of pump
more » ... ser is established. The model is used in simulation, and the simulation results are further analyzed theoretically, showing that under the same pump power, the spherical aberration is greatest when the pump beam is of 2-order super-Gaussian distribution. The spherical aberration decreases with the increase of pump distribution coefficient k (except the Gaussian distribution). With the increase of pump power, the influence of pump distribution coefficient k on spherical aberration is aggravated gradually, and the difference in spherical aberration caused by different values of distribution coefficient k increases gradually. The range of strongest laser power of the 2-order super-Gaussian distribution pump is analyzed and simulated. Under same pump power, the maximum range of the strongest laser power of 2-order super-Gaussian distribution pump is 0.3-0.63 times the Gauss radius. The research methods and conclusions obtained in this paper have universal applicability and can be used for quantitatively analyzing the temperature distributions, thermal deformations, optical path difference distributions, and spherical aberration distributions of other laser crystals. At the same time, this study also provides a theoretical reference for improving spherical aberration from the perspective of changing the distribution of pump light and the laser output characteristics.
doi:10.7498/aps.67.20180113 fatcat:y23chg3ierdsvgynkrmisne35u

PSO-SVM-Based Online Locomotion Mode Identification for Rehabilitation Robotic Exoskeletons

Yi Long, Zhi-Jiang Du, Wei-Dong Wang, Guang-Yu Zhao, Guo-Qiang Xu, Long He, Xi-Wang Mao, Wei Dong
2016 Sensors  
Locomotion mode identification is essential for the control of a robotic rehabilitation exoskeletons. This paper proposes an online support vector machine (SVM) optimized by particle swarm optimization (PSO) to identify different locomotion modes to realize a smooth and automatic locomotion transition. A PSO algorithm is used to obtain the optimal parameters of SVM for a better overall performance. Signals measured by the foot pressure sensors integrated in the insoles of wearable shoes and the
more » ... MEMS-based attitude and heading reference systems (AHRS) attached on the shoes and shanks of leg segments are fused together as the input information of SVM. Based on the chosen window whose size is 200 ms (with sampling frequency of 40 Hz), a three-layer wavelet packet analysis (WPA) is used for feature extraction, after which, the kernel principal component analysis (kPCA) is utilized to reduce the dimension of the feature set to reduce computation cost of the SVM. Since the signals are from two types of different sensors, the normalization is conducted to scale the input into the interval of [0, 1]. Five-fold cross validation is adapted to train the classifier, which prevents the classifier over-fitting. Based on the SVM model obtained offline in MATLAB, an online SVM algorithm is constructed for locomotion mode identification. Experiments are performed for different locomotion modes and experimental results show the effectiveness of the proposed algorithm with an accuracy of 96.00% ± 2.45%. To improve its accuracy, majority vote algorithm (MVA) is used for post-processing, with which the identification accuracy is better than 98.35% ± 1.65%. The proposed algorithm can be extended and employed in the field of robotic rehabilitation and assistance. category is dependent upon the EMG signals. In the work of Joshi et al., EMG data is collected from seven leg muscles while the subjects walk on the floor and ascend as well as the transition between them. Through the time-frequency representation of collected EMG data, simple if-else 81 rules with prior knowledge are applied to classify those two gait patterns and the transition [4] . Based on the collected EMG signals, six time-domain features for correlation feature analysis are used to identify different locomotion patterns, whose accuracy and stability are better than that using the method of principal component analysis (PCA) and linear discriminate analysis (LDA) [5] . An approach was proposed to detect the pattern of stair descent based on EMG to achieve the transition from level-ground walking to stair walking for the amputee's residual limb [6] . Although the EMG signal is produced prior to motion, it is not sufficient to classify several locomotion modes independently [7] . The fusion of EMG signals and ground reaction forces/moments is used as the input of a phase-dependent pattern classifier using SVM, with which the locomotion mode identification accuracy can reach 99% in the stance phase and 95% in the swing phase [8] .Young et al. proposed to combine EMG signals and signals from mechanical sensors such as IMU and load cells together, based on which a dynamics Bayesian network was used to identify basic locomotion modes such as walking, slopes and stairs to minimize the transitional error and steady state error [9] . Joshi et al. proposed to collect data with accelerometers and EMG electrodes on the dominant leg, with which LDA and SVM were used to classify normal gait patterns and the transitions between them [10]. Since EMG electrodes have to be firmly attached to the skin, it is not convenient for applications in real situations [11] . The other category is based on kinesiological signals containing kinematics information such as inclination angles and dynamics information such as force and moment signals. Ground reaction force (GRF) is collected using a wearable plantar pressure measurement system, based on which, LDA was used to achieve a good identification accuracy for several locomotion modes [12] . Although GRF can be collected easily, it only represents the interaction information between the robot and the ground, which will be invalid when the leg is located in the swing phase or on uneven surfaces [13] . The IMU can also be used to identify several gait patterns such as level ground walking, stair walking, and ramp walking with an optimized threshold method, based on which, the controller is able to identify gait modes in real time and properly control the actuation [14] . Based on previous sensor information and current sensor information of load cells and 6-axis IMU, a dynamic Bayesian network was used to identify several different gait patterns and achieve the transitions between locomotion modes [15] . In general, signals from single kind of kinematics or dynamics sensors are not sufficient for locomotion mode identification. Multisensory information has been widely used in locomotion mode identification for robots, which can improve system performance as well as robustness [16] . Based on angular positions and velocities of robots joints and interaction forces/moments between the user
doi:10.3390/s16091408 pmid:27598160 pmcid:PMC5038686 fatcat:wqfboaj7ybberph5zyuoq4m3xe

Treatments for the Fifth Metacarpal Neck Fractures

Shuang-Le Zong, Gang Zhao, Li-Xin Su, Wei-Dong Liang, Li-Geng Li, Guang Cheng, Ai-Jun Wang, Xiao-Qiang Cao, Qiu-Tao Zheng, Li-Dong Li, Shi-Lian Kan
2016 Medicine  
The fifth metacarpal neck fractures (commonly termed boxer's fractures) are the most common type of metacarpal fractures. Many types of treatments are available in clinical practice, some of which have already been compared with other treatments by various researchers. However, a comprehensive treatment comparison is lacking. We estimated the comparative efficacy of different interventions for total complications, through a network meta-analysis of randomized controlled trials. We conducted a
more » ... stematic search of the literature through October 2015. The outcome measurements were the total complications. We used a Bayesian network meta-analysis to combine direct and indirect evidence and to estimate the relative effects of treatment. We identified 6 RCTs registering a total of 288 patients who were eligible for our network meta-analysis. The literature's quality is relatively high. The median Structured Effectiveness for Quality Evaluation of Study score for the included trials was 33.8. The overall methodological quality was high. Of the 6 studies, all were 2-arm controlled trials comparing active intervention. Among the 4 treatments-conservative treatment (CT), antegrade intramedullary nailing (AIMN), transverse pinning (TP) with K-wires, and plate fixation (PF)-CT had the best rankings (ie, lowest risk of total complications), followed by PF, AIMN, and TP (ie, highest risk of total complications). Furthermore, we also presented the results using surface under the cumulative ranking curve. The surface under the cumulative ranking curve probabilities were 94.1%, 52.9%, 37.3%, and 15.7% for CT, PF, AIMN, and TP, respectively. In conclusion, current evidence suggested that conservative treatment is the optimum treatment for the fifth metacarpal neck fractures because of reduced total complication rates. Moreover, the TP with K-wires is the worst option with highly total complication rates. PF and AIMN therapy should be considered as the first-line choices. Larger and higher-quality randomized controlled trials are required to confirm these conclusions and better inform clinical decision-making.
doi:10.1097/md.0000000000003059 pmid:26986129 pmcid:PMC4839910 fatcat:iajbipdcqbdhdct6jhwr6v2qhm

Reversal of multi-drug resistance by pSUPER-shRNA-mdr1 in vivo and in vitro

Guang-Dong Pan, Jian-Qing Yang, Lv-Nan Yan, Guang-Ping Chu, Qiang Liu, Yi Xiao, Lin Yuan
2009 World Journal of Gastroenterology  
AIM: To explore the possibility of reversing multi-drug resistance (MDR) to HepG2/mdr1 in vitro and in vivo with RNA interference (RNAi). METHODS: HepG2/mdr1 was obtained by cloning the whole gene mdr1 into HepG2 cells. shRNA targeting sequence was designed to be homologous to the P-gp encoding MDR1 mRNA consensus sequence. pSUPER-shRNA/mdr1 was constructed using the enzymedigested technique. HepG2/mdr1 cells were transfected with vectors of pSUPER-shRNA/mdr1 to measure their efficacy by
more » ... me PCR for mdr1 mRNA, flow cytometry (FCM) for P-gp expression, and Rhodamine efflux, MTT method for HepG2/mdr1 function, respectively. In vivo , mice tumors were treated by injecting pSUPER-shRNA/mdr1 in situ and into intraabdominal cavity. Tumors were collected to create cell suspension and cryosections after chemothearpy with adiramycin and mytomycin. The cell suspension was incubated in RPMI-1640 supplemented with G418 to screen stable cells for appreciating the reversal of MDR. Cryosections were treated with immunohistochemistry technique to show the effectiveness of transfection and the expression of P-gp. RESULTS : pSUPER-shRNA/mdr1 was successfully constructed, which was confirmed by sequencing. The MDR phenotype of HepG2/mdr1 was decreased significantly in vitro transfection. HepG2/mdr1 showing its MDR was reversed notably in P-gp expression (11.0% vs 98.2%, P < 0.01). Real-time PCR showed that mRNA/mdr1 was lower in test groups than in control groups (18.73 ± 1.33 vs 68.03 ± 2.21, P < 0.001). Compared with HepG2, the sensitivity of HepG2/ mdr1 and HepG2/mdr1-dsRNA cells to ADM was decreased by 1.64 times and 15.6 times, respectively. The accumulation of DNR in positive groups was decreased evidently. In vivo , the p-gp expression in positive groups was significantly lower than that in control groups (65.1% vs 94.1%, P < 0.05). The tumor suppressing rate in test groups was 57.8%. After chemotherapy, the growth rate in test groups was lower than that in control groups (700.14 ± 35.61 vs 1659.70 ± 152.54, P < 0.05). Similar results were also observed under fluorescence microscope, and confirmed by Image-Pro Plus 4.5 analysis. CONCLUSION: pSUPER-shRNA/mdr1 vector system allows simple, stable and durable nonviral knockdown of P-gp by RNAi in malignant cells and animals to restore their sensitivity to adriamycin.
doi:10.3748/wjg.15.431 pmid:19152447 pmcid:PMC2653364 fatcat:oyjxkxomsze4hbzrubpvrrv3ya

Polymeric bis(N-methylformamide)tetrathiocyanatocadmium(II)mercury(II)

Xin Qiang Wang, Wen Tao Yu, Dong Xu, Guang Hui Zhang
2005 Acta Crystallographica Section E  
E61, m1147-m1149 [https://doi.org/10.1107/S1600536805015394] Polymeric bis(N-methylformamide)tetrathiocyanatocadmium(II)mercury(II) Xin Qiang Wang, Wen Tao Yu, Dong Xu and Guang Hui Zhang poly[bis(N-methylformamide  ... 
doi:10.1107/s1600536805015394 fatcat:4dvi5ulnnvhhzd2dusxxk7i42a

Sensitive chemically amplified electrochemical detection of ruthenium tris-(2,2′-bipyridine) on tin-doped indium oxide electrode

Dong Zheng, Na Wang, Fu-Quan Wang, Dong Dong, Yuan-Guang Li, Xi-Qiang Yang, Liang-Hong Guo, Jing Cheng
2004 Analytica Chimica Acta  
Optimized combination of chemical agents was selected for sensitive electrochemical detection of dissolved ruthenium tris-(2,2 -bipyridine) (Ru-bipy). The detection was based on the chemical amplification mechanism, in which the anodic current of a redox-active analyte was amplified by a sacrificial electron donor in solution. On indium-doped tin oxide (ITO) electrodes, electrochemical reaction of the analyte was reversible, but that of the electron donor was greatly suppressed. Several
more » ... on metal complexes, such as ferrocene and tris-(2,2 -bipyridine) complexes of osmium, iron and ruthenium, were evaluated as model analyte. A correlation between the amplified current and the standard potential of the complex was observed, and Ru-bipy generated the largest current. A variety of organic bases, acids and zwitterions were assessed as potential electron donor. Sodium oxalate was found to produce the largest amplification factor. With Ru-bipy as the model analyte and oxalate as the electron donor, the analyte concentration curve was linear up to 50 M, with a lower detection limit of approximately 50 nM. Preliminary work was presented in which a Ru-bipy derivative was attached to bovine serum albumin and detected electrochemically. Although the combination of Ru-bipy, oxalate and ITO electrode has been used before for electrochemiluminescent detection of Ru-bipy and oxalate, as well as electrochemical detection of oxalate, its utility in amplified voltammetric detection of Ru-bipy as a potential electrochemical label has not been reported previously.
doi:10.1016/j.aca.2003.12.002 fatcat:etbl5mugzjfw5a56rla4f5j54q

For the first time fengyun3 C satellite-global navigation satellite system occultation sounder achieved spaceborne Bei Dou system radio occultation

Wang Shu-Zhi, Zhu Guang-Wu, Bai Wei-Hua, Liu Cong-Liang, Sun Yue-Qiang, Du Qi-Fei, Wang Xian-Yi, Meng Xiang-Guang, Yang Guang-Lin, Yang Zhong-Dong, Zhang Xiao-Xin, Bi Yan-Meng (+5 others)
2015 Wuli xuebao  
图 8 展示了一对符合匹配标准的 GNOS 电离层掩 星 事 件, 蓝 实 线 为 BDS/GNOS 掩 星 电 离 层 电 子 密 度 廓 线, 红 实 线 为 GPS/GNOS 掩 星 电 子 密 度 089301-5 Du Qi-Fei 1) Wang Xian-Yi 1) Meng Xiang-Guang 1) Yang Guang-Lin 2) Yang Zhong-Dong 2) Zhang  ...  1) Bai Wei-Hua 1) † Liu Cong-Liang 1) Sun Yue-Qiang 1) ) 式可用 BDS 和 GPS 实现 LEO 卫星实时定 位, 2 1 • , 掩星事件发生时间在 1 h 之内.  ... 
doi:10.7498/aps.64.089301 fatcat:mh3hcopfg5dgxazukhhdr3k23u

4,5-Bis(pivaloylsulfanyl)-1,3-dithiolane-2-thione

Yan Ling Wang, Wen Tao Yu, Dong Xu, Xin Qiang Wang, Guang Hui Zhang
2005 Acta Crystallographica Section E  
Key indicators Single-crystal X-ray study T = 293 K Mean (C-C) = 0.006 Å R factor = 0.061 wR factor = 0.169 Data-to-parameter ratio = 18.6 For details of how these key indicators were automatically derived from the article, see
doi:10.1107/s160053680500721x fatcat:odnzxndlhvbdhlbvesofiueqlq

Electrochemical potential equilibrium of electrons in ideal metallic glasses based on the cluster-resonance model

Han Guang, Qiang Jian-Bing, Wang Qing, Wang Ying-Min, Xia Jun-Hai, Zhu Chun-Lei, Quan Shi-Guang, Dong Chuang
2012 Wuli xuebao  
Ideal metallic glasses are the metallic glasses that satisfy electronic structure stability. Previously we have developed a socalled 'cluster-plus-glue-atom model' and more recently a 'cluster-resonance model' for the ideal metallic glasses. Good metallic glass forming compositions always satisfy simple cluster formulas [cluster] (glue atoms), with x denoting the number of glue atoms matching one cluster. In this paper we present an electrochemical potential equilibrium criterion based on these
more » ... models to obtain the number of glue atoms. By examples of Cu-Zr and Co-B bulk metallic glasses, it is confirmed that the experimentally determined good BMG-forming compositions well agree with the calculated composition formulas.
doi:10.7498/aps.61.036402 fatcat:nhaqcexuinfahbrcwrgbg2elcu

4,5-Bis(phenylsulfonylthio)-1,3-dithiolane-2-thione

Yan-Ling Wang, Wen-Tao Yu, Dong Xu, Xin-Qiang Wang, Guang-Hui Zhang, Lin Feng
2005 Acta Crystallographica Section E  
E61, o1432-o1433 [https://doi.org/10.1107/S1600536805011876] 4,5-Bis(phenylsulfonylthio)-1,3-dithiolane-2-thione Yan-Ling Wang, Wen-Tao Yu, Dong Xu, Xin-Qiang Wang, Guang-Hui Zhang and Lin Feng source:  ... 
doi:10.1107/s1600536805011876 fatcat:n64nlpo77fdrnfjewcdeyn5e54
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