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温泉体应变观测数据不同频段影响因素及特征

内陆地震 2024年第3期38卷 299-306页

作者：吕国强景孝复李晓东马慧婷关冬晓新疆维吾尔自治区地震局且末地震监测中心站新疆且末841900 新疆维吾尔自治区地震局博乐地震监测中心站新疆博乐833400 新疆维吾尔自治区地震局新疆乌鲁木齐830011 且末县第一中学新疆且末841900

定点形变观测值序列包含的信息有来自地球内部的应力积累和来自地球外部的因素影响,数学物理内涵丰富。基于形变测值序列综合性与可分性的特点,将温泉体应变、气温、水位、气压进行频域分析,然后将时间序列值分解,研究温泉体应变不同频... 详细信息

定点形变观测值序列包含的信息有来自地球内部的应力积累和来自地球外部的因素影响,数学物理内涵丰富。基于形变测值序列综合性与可分性的特点,将温泉体应变、气温、水位、气压进行频域分析,然后将时间序列值分解,研究温泉体应变不同频段的影响因素,结果表明:(1)气压对温泉体应变的影响主要有2~4小时和1~2个月之间的月波两个频段;(2)水位为温泉体应变年周期频段的主要影响因素,且它们之间的相位差约为29天;(3)固体潮为影响温泉体应变半日波、日波频段的主要因素。

关键词：体应变气压水位相关系数散点图

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中国昼夜降水特征的空间分异规律

水电能源科学 2024年第4期42卷 10-14页

作者：苏桐张文江覃光华黎小东李红霞兰平四川大学水利水电学院四川成都610065

降水昼夜分配的时空特征,是干旱半干旱地区降水资源有效性的重要影响因素。我国昼夜降水空间分异复杂,在雨强、高程、季相等方面的规律还有待进一步研究。为此,采用空间分区、高程分带、雨强分级、季相对比等方法,基于全国839个气象站点... 详细信息

降水昼夜分配的时空特征,是干旱半干旱地区降水资源有效性的重要影响因素。我国昼夜降水空间分异复杂,在雨强、高程、季相等方面的规律还有待进一步研究。为此,采用空间分区、高程分带、雨强分级、季相对比等方法,基于全国839个气象站点1951~2019年的降水资料,研究了我国昼夜降水特征的空间分异规律。结果表明,在空间分区上,我国可划分为受夜间冷却和山谷风效应的青藏及周边夜雨典型区、受辐射对流效应的秦-淮以南昼雨典型区、秦-淮以北降水昼夜相对均衡区;在垂直分异方面,青藏高原及周边山地最为明显,年夜间降水量的高程递减率大于昼间,昼夜差异随海拔升高而减弱;降水的雨强特征为中高雨强降水比重大,尤其是青藏东缘中高强度夜雨显著;季相规律为青藏及西南地区月降水均为夜雨大于昼雨,而南方4~10月昼雨典型。我国昼夜降水特征的空间分异规律,可作为农业与生态水资源气候评估的参考,对山洪预警也有重要意义。

关键词：昼夜降水空间分异季相变化雨强规律海拔效应年际变化

乡村振兴视域下的廊坊市农村集体经济产业模式发展研究

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蚌埠学院学报 2024年第3期13卷 47-52页

作者：李晓东周帅牛永辉安徽科技学院人文学院安徽滁州233100 安徽科技学院管理学院安徽蚌埠233030

分析了农村集体经济在实现乡村振兴战略中扮演着的至关重要的角色。河北省廊坊市政府根据全市农村实际情况制定了农村集体经济发展规划,通过强化党建引领、优化资源配置,打造乡村振兴连片示范区等措施,致力于发展壮大廊坊市农村集体经... 详细信息

分析了农村集体经济在实现乡村振兴战略中扮演着的至关重要的角色。河北省廊坊市政府根据全市农村实际情况制定了农村集体经济发展规划,通过强化党建引领、优化资源配置,打造乡村振兴连片示范区等措施,致力于发展壮大廊坊市农村集体经济并取得突出成效。对廊坊市的各项信息进行处理和提炼,总结出廊坊市农村集体经济产业发展所呈现的“六种模式”,包括资源整合、文创旅游、品牌打造、股份合作、承包租赁以及资源开发。同时,探讨了集体经济成功发展的因素,总结了经验启示,旨在为其他地区农村集体经济发展提供一些参考。

关键词：乡村振兴战略农村集体经济发展模式

Performance evaluation of laponite as a mud-making material for drilling fluids

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Petroleum Science 2019年第4期16卷 890-900页

作者： Zheng-Qiang Xiong xiao-dong li Fan Fu Yan-Ning li Beijing Institute of Exploration Engineering

In this study, laponite was tested as a mud-making material for drilling fluids. Laponite is a synthetic smectite clay with a structure and composition closely resembling the natural clay mineral hectorite. Commercially available laponite was characterized by X-ray di ractometry, scanning electron microscopy and infrared spectrometry. Its dispersibility, salt resistance and high-temperature resistance were evaluated. The results showed that laponite possessed superior cation exchange capacity(140.4 mmol/100 g) with interlayer cations of Na^+ and li^+. Laponite could easily be dispersed in water to yield increased viscosity with no influence from hydration time or temperature. On the other hand, laponite dispersions displayed an excellent heat resistance, with invariant apparent viscosity at high temperatures. For instance, the apparent viscosity of the2 wt% laponite dispersion underwent changes between 22 and 24 mPa s after hot rolling at 180–240 °C for 16 h. Compared to existing mud-making materials, laponite exhibited better mud-making properties. Furthermore, laponite revealed good compatibility with other additives, and the water-based drilling fluids prepared with laponite as mud-making material showed an excellent stability at elevated temperatures and superior performance–cost ratios. Overall, these findings indicated that laponite had an excellent dispersibility at high temperatures and hence would have promising applications as high-temperature mud-making material for preparing water-based drilling fluids designed for ultra-high-temperature environments.

关键词： Laponite Mud-making material Dispersibility High-temperature tolerance Ultra-high-temperature water-based drilling fluids

Probabilistic Teleportation of an Unknown One-Particle State by a Three-Particle General W State

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Communications in Theoretical Physics 2007年第4期47卷 625-628页

作者： XIU xiao-Ming dong li GAO Ya-Jun Department of Physics Bohai University Jinzhou 121000 China

Two schemes for teleporting an unknown one-particle state are proposed when a general W state is utilized as quantum channel. In the first scheme, after the sender （Alice） makes a Bell-state measurement on her particles, the recipient （Bob） performs a Von Neumann measurement and introduces an auxiliary particle, and carries out a unitary transformation on his particle and the auxiliary particle, and performs a Von Neumann measurement on the auxiliary particle to confirm whether the teleportation succeeds or not. In the second scheme, the recipient （Bob） does not need to perform the first Von Neumann measurement or introduce the auxiliary particle, which is necessary in the first scheme. It is shown that the maxima/probabilities of successful teleportation of the two schemes are identical if the recipient （Bob） performs an appropriate unitary transformation and adopts a proper particle on which he recovers the quantum information of state to be teleported.

关键词： quantum information probabilistic teleportation entanglement general W state

Synthesis and mesomorphic properties of bent-shaped molecule with low bent-angle central core and long alkylthio tail

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Chinese Chemical Letters 2011年第9期22卷 1111-1114页

作者： xiao dong li Mao Sheng Zhan Kai Wang School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N（1,7）-n-OPIMB and N（1,7）-n-SP1MB （n = 20, 22）, respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry （DSC）, polarizing optical microscopy （POM） and X-ray diffraction （XRD）. Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N（1,7）-n-OPIMB, N（1,7）-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.

关键词： Bent-shaped liquid crystal Alkylthio tail Mesomorphic behaviour

On Impulsive Control for Synchronization and Its Application to Matsumoto-Chua-Kobayashi （MCK） Circuit

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Communications in Theoretical Physics 2007年第2X期48卷 275-278页

作者： li Yang liAO xiao-Feng li Chuan-dong WANG Yong College of Computer Science and Engineering Chongqing University Chongqing 400030 China

The issue of impulsive control theory for synchronization of the MCK circuit is developed. We propose an impulsive control scheme for the complete synchronization of the MCK circuit including chaotic systems. A sufficient condition for the impulsive control is derived, with an easily calculated maximum impulsive interval. The proposed impulsive control scheme is applied to the MCK circuit and the simulation result demonstrates the effectiveness of the method.

关键词： chaos impulsive control MCK circuit

Solid-state phase transformation of TC11 titanium during unstable thermal cycling in laser melting deposition process

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Journal of Iron and Steel Research International 2019年第7期26卷 743-750页

作者： xiao-dong li Jin liu Yan-yan Zhu Xu Cheng dong liu Ji-kui Zhang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and Engineering Beihang University Beijing 100191 China Beijing Yuding Additive Manufacturing Research Institute Co. Ltd. Beijing 100096 China School of Aircraft Design Beihang University Beijing 100191 China

Thermal cycling procedure during laser additive manufacturing (LAM) process causes the appearance of bright and dark patterns on the etched surface of TC11 alloy components. The formation mechanisms of these patterns and the solid-state transformation related to LAM process are systematically investigated with the predication of temperature fields using the finite element software ABAQUS. The results indicate that by increasing subsequent thermal cycles, the peak temperatures for every cycle decrease. When peak temperatures are above Tβ(phase transition temperature of β phase), which is 1010℃ in TC11 alloy, no pattern is observed. Meanwhile, a decrease in peak temperature leads to appearance of an ultrafine basket-weave α+β microstructure (dark contrast) with gradually increased amount of α colonies in the alloy. A special bimodal microstructure with ‘fork-like'α lamella appears in the layer when the peak temperatures of thermal cycles firstly fall into α+β dual-phase region. And this special bimodal microstructure gives a bright contrast and only appears at the region where the peak temperatures are below 970℃, leaving the rest region with a dark contrast. With the continuous increase in thermal cycles in α+β dual-phase region,α lamella gradually coarsens. After five thermal cycles in α+β two-phase region, no further changes in microstructure are observed, and the morphologies of α lamella in dark and bright regions are almost the same but with different amounts of α phase.

关键词： Thermal cycling Laser melting deposition TC11 Solid-state phase transformation Temperature field

A novel flotation scheme: selective flotation of tungsten minerals from calcium minerals using Pb–BHA complexes in Shizhuyuan

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Rare Metals 2017年第6期36卷 533-540页

作者： Hai-Sheng Han Wen-li liu Yue-Hua Hu Wei Sun xiao-dong li School of Mineral Processing and Bioengineering Central South University Hu Nan Shizhuyuan Non-ferrous Metal limited liability Corporation

The similar floatabilities of calcium minerals and the huge difference between scheelite and wolframite have resulted in difficulties during their separation by flotation in Shizhuyuan Mine. In this study, novel collectors, lead complexes of benzohydroxamic acid（Pb-BHA）,were introduced to modify the surface properties of scheelite and wolframite, thereby effectively and selectively improving floatability. The Pb-BHA complexes are found to be selective for the separation of scheelite and calcium minerals with little use of depressants and enable the synchronous flotation of scheelite and ***, a novel flotation process was developed for the recovery of tungsten minerals. The process is simplified greatly, and the recovery is improved by almost 10%.Removing or decreasing the amount of water glass contributes to the improvement of tungsten and fluorite recovery and the circulation of water and reagents, which benefits the environment.

关键词： Tungsten minerals Flotation Calciumminerals Benzohydroxamic acid complexes Water glass