期刊文献+
共找到229篇文章
< 1 2 12 >
每页显示 20 50 100
Rotational Analysis of A2Ⅱu-X2∑g+ System of 14N2+
1
作者 张艳平 邓伦华 +1 位作者 张静 陈扬骎 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期134-142,I0001,共10页
The absorption spectrum of N2+ has been studied using optical-heterodyne velocity mod- ulation spectroscopy in the near-infrared region. The observed spectral lines were assigned to the (3,1), (4,2), (5,3), (... The absorption spectrum of N2+ has been studied using optical-heterodyne velocity mod- ulation spectroscopy in the near-infrared region. The observed spectral lines were assigned to the (3,1), (4,2), (5,3), (8,5) bands of the A2Ⅱu-X2∑g+ system and the line lists were pro- vided. The (5,3) band was studied for the first time. Fourteen rotational-resolved bands in literatures were fitted together with our observed bands and the molecular constants were obtained for VA=0-9 and vx=0-5. 展开更多
关键词 Absorption spectroscopy rotational analysis N2
下载PDF
Treatment of C2 body fracture with unusual distractive and rotational components resulting in gross instability 被引量:3
2
作者 Darryl Lau Samuel S Shin +1 位作者 Rakesh Patel Paul Park 《World Journal of Orthopedics》 2013年第4期323-326,共4页
Cervical fractures can result in severe neurological compromise and even death. One of the most commonly injured segments is the C2 vertebrae, which most frequently involves the odontoid process. In this report, we pr... Cervical fractures can result in severe neurological compromise and even death. One of the most commonly injured segments is the C2 vertebrae, which most frequently involves the odontoid process. In this report, we present the unusual case of a 28-year-old female who sustained a C2 vertebral body fracture(comminuted transverse fracture through the body and both transverse processes) that had both a significant distractive and rotational component, causing the fracture to be highly unstable. Application of halo bracing was unsuccessful. The patient subsequently required a C1-C4 posterior spinal fusion. Follow-up computer tomography imaging confirmed fusion and the patient did well clinically thereafter. 展开更多
关键词 C2 Distractive ODONTOID FRACTURE rotational SPINE TypeⅢ Unstable
下载PDF
A Brief Study on pH, Exchangeable Ca<sup>2+</sup>and Mg<sup>2+</sup>in Farmlands under Tobacco-Rice Rotation in Xuancheng City of South Anhui 被引量:5
3
作者 Anqi Wang Ka Lin +9 位作者 Chengxin Ma Qin Gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue Chaolong Zu Chaoqiang Jiang Jia Shen Decheng Li 《Agricultural Sciences》 2018年第4期480-488,共9页
pH, exchangeable Ca2+ and Mg2+ of soil can influence the yield and quality of flue-cured tobacco. Xuancheng city is the dominant tobacco-planting region in Anhui province since 2008. A general soil survey was conducte... pH, exchangeable Ca2+ and Mg2+ of soil can influence the yield and quality of flue-cured tobacco. Xuancheng city is the dominant tobacco-planting region in Anhui province since 2008. A general soil survey was conducted in Xuancheng city to understand the current situations of pH, exchangeable Ca2+ and Mg2+ of farmlands under tobacco-rice rotation and to decide whether continuous applying dolomite powders to abate soil acidification. In total 124 topsoil samples (0-20 cm) were collected from the typical farmlands and soil pH, exchangeable Ca2+ and Mg2+ were measured. The results showed that soil pH and Ca2+ and Mg2+ in Xuancheng city were generally in the suitable grades, pH ranged from 4.56 to 8.42 with an average of 5.87, exchangeable Ca2+ ranged from 1.01 cmol(1/2Ca2+) kg-1 to 100.55 cmol(1/2Ca2+) kg-1 with an average of 11.07 cmol(1/2Ca2+) kg-1, and exchangeable Mg2+ ranged from 0.14 cmol(1/2Mg2+) kg-1 to 2.86 cmol(1/2Mg2+) kg-1 with an average of 0.81 cmol(1/2Mg2+) kg-1, all spanned from the low grades to the high grades. To the whole Xuancheng city, 37.10%, 62.10% and 72.58% of the surveyed farmlands were in the low grades of pH, exchangeable Ca2+ and Mg2+, respectively, while 52.42%, 25.00% and 20.97% of the farmlands were in the suitable grades, respectively. pH had an extremely significantly positive Napierian logarithm correlation with exchangeable Ca2+ and an extremely significantly positive power correlation with exchangeable Mg2+. In total about 338.2 kg·hm-2 of Ca2+ and 202.4 kg·hm-2 of Mg2+ are annually input into the farmlands, while about 110.4 kg·hm-2 of Ca2+ and 7.4 kg·hm-2 of Mg2+ are annually moved out from the farmlands, exchangeable Ca2+ and Mg2+ were annually increased by 225.2 kg·hm-2 and 187.6 kg·hm-2 in the farmlands, respectively. It is necessary to monitor the farmlands dynamically in order to decide whether continuous applying dolomite powders which should be dependent upon the specific conditions of individual farmlands. 展开更多
关键词 PH Exchangeable Ca2+ and Mg2+ DOLOMITE Powders Farmlands Tobacco-Rice rotation Xuancheng CITY
下载PDF
The rotational anisotropies in the ferromagnetism/antiferromagnetism 1/ antiferromagnetism 2 exchange bias structures 被引量:2
4
作者 胡经国 Stamps R L 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第7期1595-1601,共7页
The rotational anisotropies in the exchange bias structures of ferromagnetism/antiferromagnetism 1/antiferro- magnetism 2 are studied in this paper. Based on the model, in which the antiferromagnetism is treated with ... The rotational anisotropies in the exchange bias structures of ferromagnetism/antiferromagnetism 1/antiferro- magnetism 2 are studied in this paper. Based on the model, in which the antiferromagnetism is treated with an Ising mean field theory and the rotational anisotropy is assumed to be related to the field created by the moment induced on the antiferromagnetic layer next to the ferromagnetic layer, we can explain why in experiments for ferromag- netism (FM)/antiferromagntism 1 (AFM1)/antiferromagnetism 2 (AFM2) systems the thickness-dependent rotational anisotropy value is non-monotonic, i.e. it reaches a minimum for this system at a specific thickness of the first anti- ferromagnetic layer and exhibits oscillatory behaviour. In addition, we find that the temperature-dependent rotational anisotropy value is in good agreement with the experimental result. 展开更多
关键词 FM/AFM1/AFM2 trilayer rotational anisotropy exchange coupling
下载PDF
A Process-based Model of N_2O Emission from a Rice-Winter Wheat Rotation Agro-Ecosystem:Structure,Validation and Sensitivity 被引量:1
5
作者 周再兴 郑循华 +2 位作者 谢宝华 韩圣慧 刘春岩 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第1期137-150,共14页
In order to numerically simulate daily nitrous oxide (N2O) emission from a rice-winter wheat rotation cropping system, a process-based site model was developed (referred to as IAP-N-GAS) to track the movement and ... In order to numerically simulate daily nitrous oxide (N2O) emission from a rice-winter wheat rotation cropping system, a process-based site model was developed (referred to as IAP-N-GAS) to track the movement and transformation of several forms of nitrogen in the agro-eeosystem, which is affected by climate, soil, crop growth and management practices. The simulation of daily N2O fluxes, along with key daily environmental variables, was validated with three-year observations conducted in East China. The validation demonstrated that the model simulated well daily solar radiation, soil temperature and moisture, and also captured the dynamics and magnitude of accumulated rice aboveground biomass and mineral nitrogen in the soil. The simulated daily N2O emissions over all three years investigated were generally in good agreement with field observations. Particularly well simulated were the peak N2O emissions induced by fertilizations, rainfall events or mid-season drainages. The model simulation also represented closely the inter-annuM variation in N2O emission. These validations imply that the model has the capability to capture the general characteristics of N2O emission from a typical rice-wheat rotation agro-ecosystem. Sensitivity analyses revealed that the simulated N2O emission is most sensitive to the fertilizer application rate and the soil organic matter content, but it is much less sensitive to variations in soil pH and texture, temperature, precipitation and crop residue incorporation rate under local conditions. 展开更多
关键词 Nitrous oxide (N2O) modeling N cycling rice-wheat rotation
下载PDF
The g-factors and magnetic rotation in ^(82)Rb
6
作者 袁大庆 郑永男 +9 位作者 左翼 范平 周冬梅 吴晓光 竺礼华 李广生 许国基 樊启文 张锡珍 朱升云 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期207-212,共6页
The g-factors of the intra-band states 12, 13, 14, 15 in a magnetic-rotational band built on the 11 state in S2Rb are measured for the first time by using a transient magnetic field-ion implantation perturbed angular ... The g-factors of the intra-band states 12, 13, 14, 15 in a magnetic-rotational band built on the 11 state in S2Rb are measured for the first time by using a transient magnetic field-ion implantation perturbed angular distribution (TMF-IMPAD) method. The magnetic-rotational band in ^82Rb is populated by the ^60Ni(27A1,4pn)^82Rb reaction, and the time-integral Larmor precessions are measured after recoil implantation into a polarized Fe foil. The calculation of g-factors is also carried out in terms of a semi-classical model of independent particle angular momentum coupling on the basis of the four-quasiparticle configuration π(99/2)^2 Оπ(p3/2, f5/2) О v (g9/2). The measured and calculated g-factors are in good agreement with each other. The g-factors and deduced shear angles decrease with the increase of spin along the band. This clearly illustrates the shear effect of a step-by-step alignment of the valence protons and neutrons in magnetic rotation. The semi-classical calculation also shows that the alignment of the valence neutron angular momentum is faster than that of the valence protons, which results in a decrease of g-factors with increasing spin. The present results provide solid evidence of the shear mechanism of magnetic rotation. 展开更多
关键词 S2Rb magnetic rotation G-FACTOR TMF-IMPAD
下载PDF
Accurate all-electron calculation on the vibrational and rotational spectra of ground states for O2 and its ions
7
作者 Qiao-Xia Wang Yu-Min Wang +1 位作者 Ri Ma Bing Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期193-197,共5页
The potential energy curves, spectroscopic constants, and low-lying vibration–rotation levels of ground-state O2 and its cation O2+ and anion O2- were calculated with the explicitly correlated multireference configur... The potential energy curves, spectroscopic constants, and low-lying vibration–rotation levels of ground-state O2 and its cation O2+ and anion O2- were calculated with the explicitly correlated multireference configuration interaction method.The zeroth-order reference wavefunction was treated with the complete active space multiconfigurational self-consistent field method, in which the active space was carefully selected, and an additional molecular orbital πu was added into the full valence active space.The electron correlation of the 1s core in the oxygen atom was considered in the computations.The Davidson correction on molecular energy was considered to account for higher electron excitation.The relativistic effects, including the scalar relativistic effect and spin–orbit coupling, were considered in the computation of potential energy curves.These physical effects on the spectroscopic constants were examined.The low-lying levels of vibration–rotation spectra of O2 and its ions were determined based on the computed potential energy curves.Comparisons with available experiments were made and excellent agreement was obtained for the vibrational and rotational parameters.The spectroscopic constants and vibration–rotation spectrum of O2-, which is sparse in experiments, were provided.Our study will shed some light on further theoretical and experimental studies on these simple but important molecular systems. 展开更多
关键词 O2 molecule/molecular ion explicitly correlated MULTIREFERENCE configuration interaction SPECTROSCOPIC constant vibration–rotation spectrum
下载PDF
Electric-field-induced in-plane effective 90°magnetization rotation in Co2FeAl/PMN-PT structure
8
作者 Cai Zhou Dengyu Zhu +5 位作者 Fufu Liu Cunfang Feng Mingfang Zhang Lei Ding Mingyao Xu Shengxiang Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期639-643,共5页
The in-plane effective 90°magnetization rotation of Co_(2) FeAl thin film grown on PMN-PT substrate induced by the electric field is investigated at room temperature.The magnetic hysteresis loops under different ... The in-plane effective 90°magnetization rotation of Co_(2) FeAl thin film grown on PMN-PT substrate induced by the electric field is investigated at room temperature.The magnetic hysteresis loops under different positive and negative electric fields are obtained,which reveals remanent magnetization can be mediated by the electric field.Moreover,under positive electric fields,the obvious 90°magnetization rotation can be observed,while remanent magnetization is nearly unchanged under negative electric fields.The result is consistent with the electric field dependence of effective magnetic field,which can be attributed to the piezostrain effect in Co_(2) FeAl/PMN-PT structure.In addition,the piezostrain-mediated 90°magnetization rotation can be demonstrated by the result of resonance field changing with electric field in the measurement of ferromagnetic resonance,which is promising for the design of future multiferroic devices. 展开更多
关键词 electric field 90° magnetization rotation Co_(2)FeAl/PMN-PT structure
下载PDF
Rotation Stabilises 2D Skyrmions
9
作者 Rossen Dandoloff 《Journal of Modern Physics》 2020年第9期1326-1329,共4页
We present a study of 2D Skyrmions under rotation. The purpose of this study is to establish the result of the rotation on the stability of 2D Skyrmions. Usually the 2D skyrmions are metastable unless the underlying g... We present a study of 2D Skyrmions under rotation. The purpose of this study is to establish the result of the rotation on the stability of 2D Skyrmions. Usually the 2D skyrmions are metastable unless the underlying geometry introduces a characteristic length or e.g. magnetic fifield is present in the problem. We have used a previous study of the rotating plane which proves the appearance of curvature as a result of the rotation. The curvature of the rotating disk introduces length and plays here the role of strength of the angular momentum of the field. We have shown that this additional length scale introduced by the curvature stabilises the 2D Skyrnions under 展开更多
关键词 2D Skyrmions STABILITY rotationS
下载PDF
7元旋转对称2-弹性函数的构造
10
作者 杜蛟 李琳 +2 位作者 赵紫薇 李月月 王天银 《通信学报》 EI CSCD 北大核心 2024年第1期194-200,共7页
基于旋转对称轨道的数对分布矩阵的性质,给出了所有7元旋转对称2-弹性函数的具体构造。结果表明,在F_(2)^(7)上有且仅有280个非线性旋转对称2-弹性函数。进一步地,对于任意的奇数k,在F_(2)^(7k)上至少有280个非线性旋转对称2-弹性函数。
关键词 密码学 旋转对称函数 弹性函数 支撑矩阵 数对分布矩阵
下载PDF
Carbon Dioxide, Methane, and Nitrous Oxide Emissions from a Rice-Wheat Rotation as Affected by Crop Residue Incorporation and Temperature 被引量:29
11
作者 ZOU Jianwen(邹建文) +7 位作者 HUANG Yao(黄耀) ZONG Lianggang(宗良纲) ZHENG Xunhua(郑循华) WANG Yuesi(王跃思) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第5期691-698,共8页
Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and ... Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and wheat straw were incorporated into the soil at a rate of 2.25 t hm(-2) when the rice crop was transplanted in June 2001. Compared with the control, the incorporation of rapeseed cake enhanced the emissions of CO2, CH4, and N2O in the rice-growing season by 12.3%, 252.3%, and 17.5%, respectively, while no further effect was held on the emissions of CO2 and N2O in the following wheat-growing season. The incorporation of wheat straw enhanced the emissions of CO2 and CH4 by 7.1% and 249.6%, respectively, but reduced the N2O emission by 18.8% in the rice-growing season. Significant reductions of 17.8% for the CO2 and of 12.9% for the N2O emission were observed in the following wheat-growing season. A positive correlation existed between the emissions of N2O and CO2 (R-2 = 0.445, n = 73,p < 0.001) from the rice-growing season when N2O was emitted. A trade-off relationship between the emissions of CH4 and N2O was found in the rice-growing season. The CH4 emission was significantly correlated with the CO2 emission for the period from rice transplantation to field drainage, but not for the entire rice-growing season. In addition, air temperature was found to regulate the CO2 emissions from the non-waterlogged period over the entire rice-wheat rotation season and the N2O emissions from the nonwaterlogged period of the rice-growing season, which can be quantitatively described by an exponential function. The temperature coefficient (Q(10)) was then evaluated to be 2.3+/-0.2 for the CO2 emission and 3.9+/-0.4 for the N2O emission, respectively. 展开更多
关键词 emissions of CO2 CH4 and N2O rice-wheat rotation incorporation of crop residues temperature
下载PDF
Differential mRNA Expression of <i>COX</i>-2 and Proinflammatory Mediators in Patients with Rotator Cuff Tears and Osteoarthritis of the Hip 被引量:1
12
作者 Tomonori Kenmoku Kentaro Uchida +8 位作者 Naoshige Nagura Hisako Fujimaki Mitsufumi Nakawaki Naonobu Takahira Kensuke Fukushima Ryo Tazawa Kyoko Muneshige Gen Inoue Masashi Takaso 《Open Journal of Orthopedics》 2019年第11期254-263,共10页
Purpose: Bursal inflammation is thought to be a major cause of pain in degenerative rotator cuff tears (RCTs). While the expression of proinflammatory mediators, such as COX-2, TNF-α, IL-1β, and IL-6, is crucial for... Purpose: Bursal inflammation is thought to be a major cause of pain in degenerative rotator cuff tears (RCTs). While the expression of proinflammatory mediators, such as COX-2, TNF-α, IL-1β, and IL-6, is crucial for the pathophysiology of osteoarthritis (OA), their role in degenerative RCTs remains unknown. The aim of this study was to determine the expression of COX-2 and proinflammatory mediators in the development of RCT-induced pain by comparing their levels in patients with hip OA or RCTs. Methods: We included samples obtained from 31 shoulders of 31 patients with RCTs and samples from 30 hips of 27 patients with hip OA. The mRNA levels of COX-2, TNF-α, IL-1β, and IL-6 were determined using RT-PCR, and were compared between the subacromial bursa and hip joints. We also analyzed IL-1β-induced COX-2 expression in the subacromial bursa and synovial blast of the hip. Results: COX-2, IL-1β, and IL-6 expression levels were significantly lower in the subacromial bursa of RCTs than in hip OA samples, while no significant difference was observed for TNF-α. No significant difference in the fold increase was observed between subacromial bursa and hip OA samples, even though IL-1β-induced COX-2 expression increased in both samples. Conclusion: Our findings suggest that the main mechanism underlying pain development differs between patients with RCTs and those with hip OA. 展开更多
关键词 rotatOR CUFF Tear Pain HIP OSTEOARTHRITIS Tumor Necrosis Factor-α Interleukin (IL)-1β COX-2 IL-6
下载PDF
An Evaluation of Metronidazole Degradation in a Plasma-Assisted Rotating Disk Reactor Coupled with TiO2 in Aqueous Solution 被引量:1
13
作者 Yong Cai Guang-Wen Chu +4 位作者 Yong Luo Meng-Jun Su Bao-Ju Wang Bao-Chang Sun Jian-Feng Chen 《Engineering》 SCIE EI 2021年第11期1603-1610,共8页
Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward... Pollution involving pharmaceutical components in bodies of water is an increasingly serious environmental issue.Plasma discharge for the degradation of antibiotics is an emerging technology that may be relevant toward addressing this issue.In this work,a plasma-assisted rotating disk reactor(plasma-RDR)and a photocatalyst—namely,titanium dioxide(TiO_(2))—were coupled for the treatment of metronidazole(MNZ).Discharge uniformity was improved by the use of a rotating electrode in the plasma-RDR,which contributed to the utilization of ultraviolet(UV)light radiation in the presence of TiO_(2).The experimental results showed that the degradation efficiency of MNZ and the concentration of generated hydroxyl radicals respectively increased by 41%and 2.954 mg∙L^(-1) as the rotational speed increased from 0 to 500 r∙min^(-1).The synergistic effect of plasma-RDR plus TiO_(2) on the generation of hydroxyl radicals was evaluated.Major intermediate products were identified using three-dimensional(3D)excitation emission fluorescence matrices(EEFMs)and liquid chromatography-mass spectrometry(LC-MS),and a possible degradation pathway is proposed herein.This plasma-catalytic process has bright prospects in the field of antibiotics degradation. 展开更多
关键词 Plasma-assisted rotating disk reactor Pulsed discharge METRONIDAZOLE DEGRADATION TiO_(2)
下载PDF
2D-HIDDEN MARKOV MODEL FEATURE EXTRACTION STRATEGY OF ROTATING MACHINERY FAULT DIAGNOSIS 被引量:1
14
作者 YE Dapeng DING Qiquan WU Zhaotong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第1期156-158,共3页
A new feature extraction method based on 2D-hidden Markov model(HMM) is proposed. Meanwhile the time index and frequency index are introduced to represent the new features. The new feature extraction strategy is tes... A new feature extraction method based on 2D-hidden Markov model(HMM) is proposed. Meanwhile the time index and frequency index are introduced to represent the new features. The new feature extraction strategy is tested by the experimental data that collected from Bently rotor experiment system. The results show that this methodology is very effective to extract the feature of vibration signals in the rotor speed-up course and can be extended to other non-stationary signal analysis fields in the future. 展开更多
关键词 Fault diagnosis rotating machinery 2D-hidden Markov model(HMM)Feature extraction
下载PDF
水稻生长季CO_(2)通量的时间动态和影响因子研究
15
作者 张丽君 胡凝 +4 位作者 刘珊珊 徐敏 王伟 邰久 葛培 《环境科学与技术》 CAS CSCD 北大核心 2024年第3期27-36,共10页
为了明确长三角地区稻麦轮作生态系统中水稻生长季CO_(2)通量的多时间尺度变化特征,量化环境因子对农田CO_(2)通量变化的贡献度,拆分环境因子的直接影响和间接影响,该研究利用涡度相关观测系统进行了2年CO_(2)通量的连续观测,分析了辐... 为了明确长三角地区稻麦轮作生态系统中水稻生长季CO_(2)通量的多时间尺度变化特征,量化环境因子对农田CO_(2)通量变化的贡献度,拆分环境因子的直接影响和间接影响,该研究利用涡度相关观测系统进行了2年CO_(2)通量的连续观测,分析了辐射类、温度类、水汽类和风速对CO_(2)通量的影响。结果表明:稻麦轮作生态系统在水稻生长季是一个二氧化碳汇,2020、2021年水稻生长季的总固碳量分别为396.3、491.9 g/m^(2)(以C计);CO_(2)通量也有明显的日变化,呈现出“U形”和“V型”的单峰曲线,吸收峰值出现在第200~250天。在不同时间尺度上,影响CO_(2)通量的主控因子始终是光合有效辐射;但随时间尺度的增加,各个因子贡献度的差异逐渐减小。饱和水汽压差也是影响CO_(2)通量的重要因子,它与光合有效辐射的交互作用会抑制彼此对CO_(2)通量的直接贡献。 展开更多
关键词 稻麦轮作生态系统 CO_(2)通量 贡献度 交互作用 涡度相关
下载PDF
腹部注射胰岛素轮转工具与临床护理路径单在T2DM血糖管理中应用
16
作者 陈甫香 邓书英 刘春燕 《安徽医专学报》 2024年第2期146-148,共3页
目的:探讨自制腹部注射胰腺素轮转工具与临床护理路径单在2型糖尿病血糖管理中的应用效果。方法:选取医院收治的72例2型糖尿病患者,采用Excel表格进行随机数表法分为对照组(36例,常规护理干预)与观察组(36例,自制腹部注射胰岛素轮转工... 目的:探讨自制腹部注射胰腺素轮转工具与临床护理路径单在2型糖尿病血糖管理中的应用效果。方法:选取医院收治的72例2型糖尿病患者,采用Excel表格进行随机数表法分为对照组(36例,常规护理干预)与观察组(36例,自制腹部注射胰岛素轮转工具联合临床护理路径单干预),比较两组血糖水平、健康知识掌握情况及依从性。结果:观察组患者空腹血糖、餐后2 h血糖水平低于对照组(P<0.05);观察组患者健康知识评分高于对照组(P<0.05);观察组患者饮食依从性、胰岛素注射依从性、遵医依从性评分高于对照组(P<0.05)。结论:针对2型糖尿病患者血糖管理时,采用自制腹部注射胰岛素轮转工具与临床护理路径单能够提高患者健康知识掌握程度与依从性,有效控制血糖水平。 展开更多
关键词 2 型糖尿病 血糖管理 自制腹部注射胰岛素轮转工具 临床护理路径单
下载PDF
Ge掺杂增强Ruddlesden-Popper结构准二维Sr_(3)Sn_(2)O_(7)陶瓷杂化非本征铁电性的物理机制
17
作者 肖志峰 王守宇 +3 位作者 戴雅婷 康新淼 张振华 刘卫芳 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第14期246-257,共12页
准二维的杂化非本征铁电体在实现强磁电耦合的单相室温多铁性方面具有很大的潜力,然而此类陶瓷样品通常有着较高的矫顽场和较低的剩余极化强度,严重阻碍了对其的研究和应用.本文成功制备了质量高且单相性较好的具有准二维结构的双层R-P(... 准二维的杂化非本征铁电体在实现强磁电耦合的单相室温多铁性方面具有很大的潜力,然而此类陶瓷样品通常有着较高的矫顽场和较低的剩余极化强度,严重阻碍了对其的研究和应用.本文成功制备了质量高且单相性较好的具有准二维结构的双层R-P(Ruddlesden-Popper)型氧化物Sr_(3)Sn_(2–x)Ge_(x)O_(7)陶瓷样品,观察到了较高的剩余极化和与Sr_(3)Sn_(2)O_(7)单晶接近的矫顽场.微量Ge元素对B位Sn掺杂后极化强度显著增强,同时进一步降低了Sr_(3)Sn_(2)O_(7)样品的矫顽场.结合晶格动力学研究,对样品的拉曼和红外光谱进行标定,得出掺杂样品铁电性能的增强可能源于氧八面体倾侧幅度的增大和旋转幅度减小.Berry相位法和玻恩有效电荷模型进一步证实了铁电性能的增强.通过紫外可见光光度计测试得到Sr_(3)Sn_(2)O_(7)样品的光学带隙为3.91 eV,采用Becke-Johnson势结合局部密度近似(MBJ-LDA)所计算的结果与实验基本一致.总之,这项研究为此类杂化非本征铁电体的制备及铁电性能的调控提供了参考,有望促进铁电陶瓷在各种电容器和非易失性存储器件中的广泛应用. 展开更多
关键词 Sr_(3)Sn_(2)O_(7) 杂化非本征铁电性 氧八面体倾转 第一性原理计算
下载PDF
具有连续转轴的对称2R1T三自由度并联机构型综合 被引量:12
18
作者 李仕华 田志立 +1 位作者 王子义 韩雪艳 《机械工程学报》 EI CAS CSCD 北大核心 2017年第23期74-82,共9页
为综合出更多具有连续转轴的并联机构新机型,提出一种具有连续转轴的两转一移(2R1T)并联机构型综合新方法。运用螺旋理论,给出该类机构约束螺旋的空间布置,提出并联机构连续转轴的判别条件,确定分支运动副类型及空间位置关系。基于分支... 为综合出更多具有连续转轴的并联机构新机型,提出一种具有连续转轴的两转一移(2R1T)并联机构型综合新方法。运用螺旋理论,给出该类机构约束螺旋的空间布置,提出并联机构连续转轴的判别条件,确定分支运动副类型及空间位置关系。基于分支约束力与分支运动副之间的几何位置关系,证明了该类机构能够实现连续转动。利用该方法对具有平面上任意直线为连续转轴的对称两转一移并联机构进行综合,并仿真验证了研究结果的正确性。该综合方法简单、有效。 展开更多
关键词 并联机构 两转一移 连续转动 连续转轴
下载PDF
喷射式超重力旋转床吸收CO_2的研究 被引量:6
19
作者 高升 刘学军 +4 位作者 王广全 李育敏 张海燕 杨守斌 计建炳 《化工进展》 EI CAS CSCD 北大核心 2011年第S1期822-824,共3页
采用MA水溶液作为吸收剂,在超重力旋转床上进行CO_2吸收实验,考察了转子转速、吸收温度、吸收剂流量、气体流量、吸收剂中CO_2浓度等因素对CO_2吸收速率的影响。实验结果表明:当吸收温度为40℃、吸收剂流量为1 m^3/h、气体流量为12 m^3/... 采用MA水溶液作为吸收剂,在超重力旋转床上进行CO_2吸收实验,考察了转子转速、吸收温度、吸收剂流量、气体流量、吸收剂中CO_2浓度等因素对CO_2吸收速率的影响。实验结果表明:当吸收温度为40℃、吸收剂流量为1 m^3/h、气体流量为12 m^3/h、转速为1000 r/min时,吸收速率达到158.35 mol/s。 展开更多
关键词 超重力旋转床 MA MDEA 吸收 二氧化碳
下载PDF
土壤温度对北京旱地农田N_2O排放的影响 被引量:57
20
作者 谢军飞 李玉娥 《中国农业气象》 CSCD 2005年第1期7-10,共4页
在作物生长期内,通过田间自动采样系统的测定和室内温湿模拟实验,对北京地区麦豆轮作生态系统的N2O排放进行了初步研究.结果表明:在10~30℃范围内,随着土壤表层温度的升高,麦豆轮作生态系统的N2O排放通量在不同程度上有一定的增加,但... 在作物生长期内,通过田间自动采样系统的测定和室内温湿模拟实验,对北京地区麦豆轮作生态系统的N2O排放进行了初步研究.结果表明:在10~30℃范围内,随着土壤表层温度的升高,麦豆轮作生态系统的N2O排放通量在不同程度上有一定的增加,但不呈明显的线性相关关系. 展开更多
关键词 土壤温度 轮作 旱地农田 N2O排放 土壤表层 作物生长期 田间 北京 增加 影响
下载PDF
上一页 1 2 12 下一页 到第
使用帮助 返回顶部