1,599 research outputs found
Preliminary study on a predacious natural enemy, Broad vein-longitudinal striped ladybug Brumoides lineatus (Weise)
Get PDFOriginating text in Chinese.Citation: Weng, Wenshen, Huang, Yuqing. (1988). Preliminary study on a predacious natural enemy, Broad vein-longitudinal striped ladybug Brumoides lineatus (Weise). Entomological Knowledge, 25, 105-108
Foreign direct investment and China's bilateral intra-industry trade with Japan and the US
Get PDFThis paper analyzes dynamic changes of China's intra-industry trade with its major trading partners, Japan and the US, from 1980 to 2004. It also investigates to what extent foreign direct investment promoted intra-industry trade. The empirical results show that, while shares of China's intra-industry trade with both Japan and U.S rose substantially, its intra-industry trade with Japan has reached 35 per cent of the overall trade, considerably larger than 10 per cent with the US. Sino-Japan intra-industry trade concentrated in the electrical and machinery sectors accounted for 52 per cent and 46 per cent of overall trade respectively. On the other hand, it is in the chemical and food sectors where intra-industry trade represented a relatively large proportion of Sino-US trade, 50 per cent and 30 per cent accordingly in each sector. In addition, the analysis indicates that Japanese direct investment in China performed a significant role in enhancing intra-industry trade between Japan and China. However, it found no evidence that the US direct investment in China contributed to the growth of the bilateral intra-industry trade between the two countries.intra-industry trade; FDI; China
Effect of wing flexibility on aircraft flight dynamics
Get PDFThe purpose of this thesis is to give a preliminary investigation into the effect of wing deformation on flight dynamics. The candidate vehicle is FW-11 which is a flying wing configuration aircraft with high altitude and long endurance characteristics. The aeroelastic effect may be significant for this type of configuration. Two cases, the effect of flexible wing on lift distribution and on roll effectiveness during the cruise condition with different inertial parameters are investigated.
For the first case, as the wing bending and twisting depend on the interaction between the wing structural deflections and the aerodynamic loads, the equilibrium condition should be calculated. In order to get that condition, mass, structure characteristics and aerodynamic characteristics are estimated first. Then load model and aerodynamic model are built. Next the interaction calculation program is applied and the equilibrium condition of the aircraft is calculated. After that, effect of wing flexibility on lift parameters is investigated. The influence of CG, location of lift and location of flexural axis are investigated.
The other case is to calculate the transient roll rate response and estimate the rolling effectiveness of flexible aircraft, and compared with the rigid aircraft’s. A pure roll model is built and derivatives both for the rigid wing and the flexible wing are estimated. It has been found that flexible wing leads to the loss of control effectiveness, even cause reversal when reduces the structure natural frequency. The influence of inertia data for flexible roll is also investigated
Spininola yuqingensis Huang & Yu & Hu 2022, sp. n.
No full textSpininola yuqingensis sp. n. (Figs 1–3) Type material. Holotype. male, Yuqing county, 876 m, Zunyi, Guizhou Prov., 23–24.vii.2021, coll. Yan-Qing Hu & Yong Yu. Paratypes. 3 males, with the same data as the holotype; 2 males, Yuqing county, 777 m, Zunyi, Guizhou Prov., 31.vii.2021, coll. Yan-Qing Hu & Yong Yu; 4 males, Yuqing county, 876 m, Zunyi, Guizhou Prov., 29.vii.2021, coll. YanQing Hu & Yong Yu. Diagnosis. The new species resembles Spininola nepali László, Ronkay & Ronkay, 2014 by the forewing patterns, but the two species can be easily distinguished by the configurations of the male genitalia. Compared with S. nepali, the new species has a slender uncus, a wide distally and long dorsal lobe of valva and a slightly sclerotized ventral lobe of valva. Spininola nepali has a short and pointed uncus, a short dorsal lobe of valva with a parallel margin distally and a short ventral lobe of valva with a strongly sclerotized and curved margin. Description. Adult (Fig. 1). Wingspan 14–17 mm. Head grayish white; antenna brown, bipectinate in male; labial palpus short, stretched forward, mostly covered with grayish scales. Thorax brown, collar gray. Abdomen brown. Forewing ground color grayish brown, costal margin brown from medial line to wing base, vein Sc black from antemedial line to wing base, terminal area pale brown; basal line undistinguished; antemedial line blackish brown; medial line poorly visible; postmedial line wavy, formed with black dots; subterminal line wavy, formed with black and short lines; terminal line blackish brown; cilia reddish brown. Hindwing unicolorous, grayish brown; discal spot gray. Male genitalia (Figs 2 & 3). Uncus slender, pointed at apex, almost as long as the spines located at top of ventral lobe of valva; tegumen thin, about 3x as long as uncus; valva divided at base; dorsal lobe broad distally, slender at base, two thirds sclerotized at costal margin; ventral lobe slightly sclerotized with parallel margin, a spine located at apex; harpe slender, S-shaped, sclerotized; sacculus 1/3x as long as the ventral lobe of valva; saccus small and V-shaped. Aedeagus long, slightly twisted; vesica without cornuti; coecum almost 1/5 × as long as aedeagus. Female. Unknown. Distribution. China (Guizhou). Etymology. The species name is derived from the name of the type-locality.Published as part of Huang, Zhen-Fu, Yu, Yong & Hu, Yan-Qing, 2022, Description of a new species of Spininola László, Ronkay & Witt, 2010 (Lepidoptera, Nolidae, Nolinae), with new records of Spininola in China, pp. 598-600 in Zootaxa 5195 (6) on page 598, DOI: 10.11646/zootaxa.5195.6.8, http://zenodo.org/record/722399
Manganese- and rhenium-catalyzed C–H enaminylation: expedient access to novel indole–purine hybrids with anti-tumor bioactivities
No full textThe Association of Waist Circumference With Functional Mobility Among Adults With Obesity and Knee Osteoarthritis
No full textAbstract
Date Presented 3/30/2017
We examined to what extent high waist circumference was linked with decreased functional mobility over 4 yr in adults with knee osteoarthritis (OA). Measuring waist circumference may better stratify the risk of decreased functional mobility among adults with obesity and knee OA.
Primary Author and Speaker: Simone Gill
Contributing Authors: Gregory E. Hicks, Yuqing Zhang, Jingbo Niu, Caroline M. Apovian, Daniel K. White</jats:p
Robust vibration control of uncertain flexible structures based on model reduction
No full textThis paper considers robust vibration control of uncertain flexible structures. It firstly uses finite element method (FEM) to formulate the model and then reduces the degrees of freedom by employing mode truncation method. It compares the control effects of different number of modes reserved, and presents the principle of determining the number of modes truncated. Then it chooses the number and optimal place of actuators by using genetic algorithm (GA). Taking into account uncertainties which are caused by model parameter variations, a robust controller is designed to suppress the vibration of the flexible structure. The effectiveness of the methods is illustrated through numerical simulations. ? 2014 TCCT, CAA.EI
Neutral 4π-electron tetrasilacyclobutadiene contains unusual features of a Möbius-type aromatic ring
No full textAbstract The search for stable compounds containing an antiaromatic cyclic 4π system is a challenge for inventive chemists that can look back on a long history. Here we report the isolation and characterization of the novel 4π-electron tetrasilacyclobutadiene, an analogue of a 4π neutral cyclobutadiene that exhibits surprising features of a Möbius-type aromatic ring. Reduction of RSiCl3 (R = ( i Pr)2PC6H4) with KC8 in the presence of cycloalkyl amino-carbene (cAAC) led to the formation of corresponding silylene 1. Compound 1 shows further reactivity when treated with RSiCl3 under reducing conditions resulting in the formation of unsymmetrical bis-silylene 2, which was isolated as a dark red crystalline solid. Compound 3 was obtained when chlorosilylene was reduced with potassium graphite in the presence of 2. Although 3 is, according to Hückel’s rule an antiaromatic system it possesses significant aromatic character due to the unusual delocalization of the HOMO-1 and the loss of degeneracy of the higher-lying π MOs. The aromatic character of 3 is indicated by the structural stability of the compound by the very similar Si-Si bond lengths and by the NICS values. There is an unusual π conjugation between the 4 π electrons in the nearly square-planar Si4 ring where the delocalization of the HOMO-1 occurs at two opposite sides of the ring. The reversal of the π conjugation resembles the twisting of the π conjugation in Möbius aromatic systems and it contributes to the stability of the compound
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