共查询到20条相似文献，搜索用时 375 毫秒
1.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｐｈｙｓｉｃｓｏｆａｖｏｒｔｅｘｌａｔｔｉｃｅ (ＶＬ)ｉｎｔｙｐｅ ＩＩｓｕｐｅｒｃｏｎｄｕｃｔｏｒｓｈａｓｂｅｅｎｔｈｅｆｏｃｕｓｏｆｉｎｔｅｒｅｓｔｓｉｎｃｅｔｈｅｂｅｇｉｎｎｉｎｇｏｆｈｉｇｈ Ｔｃ ｒｅｓｅａｒｃｈ .Ｉｔｉｓｗｅｌｌ ｋｎｏｗｎｔｈａｔ,ａｆｔｅｒｔｈｅｅｘｔｅｒｎａｌｍａｇｎｅｔｉｃｆｉｅｌｄｅｘｃｅｅｄｓｉｔｓｃｒｉｔｉｃａｌｖａｌｕｅＨｃ1 ,ｔｈｅｍａｇｎｅｔｉｃｆｉｅｌｄｃａｎｐｅｎｅｔｒａｔｅａｔｙｐｅ ＩＩｓｕｐｅｒｃｏｎｄｕｃｔｏｒｉｎ… 相似文献
2.
The properties of a two-dimensional vortex system with random columnar defects were studied by cooling the vortex system to
zero temperature. The vortex lattice became more and more disordered with increasing pinning strengthf
p. At smallf
p, a triangular vortex, lattice away from the pins was observed. The peak of structure factorS(G0) of the vortex lattice decreased with pinning strengthf
p, which accorded with the finding that the probability of vortex to be pinned increased withf
p. Some of our results agreed with experimental findings.
Project supported by the Ministry of Science and Technology of China (NKBRSF-G19990646) and Zhejiang Province Scientific Foundation
(199031). 相似文献
3.
The superconductor sample had periodic distribution of pinned region (with length ofL
p) and unpinned region (with length ofL−L
p) along the driving force direction. Numerical study on the influence of the distribution of pinning centers on pinning of
the two-dimensional vortex system showed that the critical depinning forceF
c, beyond which the vortex system begins to depin, increases with increase ofL
p, indicating that the homogeneity of pinning centers helps to enhance the critical electric current of a superconductor. We
found that the critical depinning forceF
c depends logarithmically onL/L
p.
Project supported by the Ministry of Science and Technology of China (NKBRSF-G19990646) and Zhejiang Proviace Foundation (199031). 相似文献
4.
ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｒｅｃｅｎｔｙｅａｒｓ,ｏｒｔｈｏｇｏｎａｌｐｏｌｙｎｏｍｉａｌｓａｎｄｆｕｎｃｔｉｏｎｓｄｅｖｅｌｏｐｅｄｂｙＣｈａｎｇｅｔａｌ.( 1 986)ｈａｖｅｂｅｅｎｓｕｃｃｅｓｓｆｕｌｌｙａｐｐｌｉｅｄｉｎｔｈｅｆｉｅｌｄｏｆｄｙｎａｍｉｃｓｙｓｔｅｍｓ,ｆｏｒａｎａｌｙｓｉｓａｎｄｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆｌｉｎｅａｒｓｙｓｔｅｍｓａｎｄｔｈｅｏｐｔｉｍａｌｃｏｎｔｒｏｌ (Ｔｓａｙｅｔａｌ.,1 987) .Ｔｈｅｍａｉｎａｄｖａｎｔａｇｅｏｆｔｈｉｓｔｅｃｈｎｉｑｕｅｉｓｔｈｅ… 相似文献
5.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｎａｎｏｐａｒｔｉｃｌｅＣａＣＯ3ｈａｓａｔｔｒａｃｔｅｄｍｏｒｅａｎｄｍｏｒｅｒｅｓｅａｒｃｈｉｎｔｅｒｅｓｔｂｅｃａｕｓｅｏｆｉｔｓｂｒｏａｄａｐｐｌｉｃａｔｉｏｎｓｉｎｉｎｄｕｓｔｒｉａｌｆｉｅｌｄｓ.Ｍａｎｙｒｅｓｅａｒｃｈｅｒｓｔｒｉｅｄｔｏｅｘｐｌａｉｎｔｈｅａｂｎｏｒｍａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｎａｎｏｍａｔｅｒｉａｌｆｒｏｍｔｈｅｖｉｅｗｐｏｉｎｔｏｆｔｈｅｃｒｙｓｔａｌｓｔｒｕｃｔｕｒｅａｎｄｃｒｙｓｔａｌｉｎｔｅｒｆａｃｉａｌｖｏｌｕｍ… 相似文献
6.
ＩＮＴＲＯＤＵＣＴＩＯＮＯｖｅｒｔｈｅｐａｓｔ 1 0ｙｅａｒｓ,ｔｈｅｓｅｍｉｃｏｎｄｕｃｔｏｒＴｉＯ2 ａｓａｐｒｏｍｉｓｉｎｇｐｈｏｔｏｃａｔａｌｙｓｔｈａｓｂｅｃｏｍｅｔｈｅｆｏｃｕｓｏｆｎｕｍｅｒｏｕｓｓｔｕｄｉｅｓｏｗｉｎｇｔｏｉｔｓｓｔａｂｉｌｉｔｙｉｎｖａｒｉｏｕｓｓｏｌｖｅｎｔｓｕｎｄｅｒｐｈｏｔｏｉｒｒａｄｉａｔｉｏｎ ,ｓｕｉｔａｂｌｅｒｅｄｏｘｐｏｔｅｎｔｉａｌａｎｄｍａｎｙｅｎｖｉｒｏｎｍｅｎｔａｌａｐｐｌｉｃａ ｔｉｏｎｓ,ｓｕｃｈａｓｓｏｌａｒｅｎｅｒｇｙｃｏｎｖｅｒｓｉｏｎ… 相似文献
7.
This paper presents the simulation results of the wind environment around a single high-rise building and that around two tall buildings in tandem arrangement by using the lattice Boltzmann method with an aim to understand the ventilation issues around high-rise buildings in an urban environment. We analyzed the velocity distribution around the buildings and performed numericl simulations to reveal the formation and evolution law of the complex vortex system around the high-rise buildings. Numerical simulation results manifest a periodicity phenamenon in the process of the vortex evolution. For the case of two high-rise buildings, wind velocity in the space between the two buildings is very small, which is nearly a silent regime. Wind velocity above the front building is relatively larger and the maximum wind velocity is approximately 2.5 times the incoming wind velocity. The numerical results can be used in layout planning of high-rise residential buildings to create better environment for ventilation purpose in an urban area. 相似文献
8.
INTRODUCTION A number of problems involve flows of gases orliquids over bluff bodies such as air flowing over carsand airplanes and wind blowing over bridges andbuildings. Many experiments or simulations havefocused on the above problems. In those phenomena,flows will not follow the solid bodies completely, butseparate from them and create wakes. The generationand shedding of large coherent vortex structures dueto flow separation make the bluff body flows complexand very difficult … 相似文献
9.
The lattice Boltzmann method (LBM) is employed to simulate the uniform flow past a circular cylinder. The performance of the two-dimensional LBM model on the prediction of force coefficients and vortex shedding frequency is investigated. The local grid refinement technique and second-order boundary condition for curved walls are applied in the calculations. It is found that the calculated vortex shedding frequency, drag coefficient and lift coefficient are consistent with experimental results at Reynolds nu... 相似文献
10.
金惠敏 《首都师范大学学报(社会科学版)》2002,(1)
叔本华将康德的“自在之物”原创性地置换为他自己的“意志” ,这在西方哲学史上不啻又一次哥白尼革命 ,德国哲学由此而走上了一条非理性主义的道路。不过 ,这一革命的完成并非轻而易举 :叔本华必须证明不可知的“自在之物”在被说成是“意志”之后如何是可知的。本文梳理和评论了叔本华研究者对“意志”之可知性的怀疑、批评和修正 ,并展示了叔本华自己在解决这一问题时的武断和犹豫 ,最后试图说明 ,问题之关键不是学术性的 ,而是在学术性之后所隐藏的思想动机和历史意图。本文所涉及的论争可能对认识中国哲学史上理学与心学之争有一定参考作用。 相似文献
11.
The present study seeks to understand the evidence base of coping‐related content (pins) shared by followers of the National Association of School Psychologists (NASP) on Pinterest. NASP's Pinterest followers are pinning professionally, but the efficacy of the content being shared is largely unknown. Using a component analysis approach, the present study links pins to common components of evidence‐based coping skills interventions. The results suggest followers of NASP on Pinterest are pinning common coping intervention components. In general, more pins are limited in evidence base, but this varies by component. Certain components are more likely to be evidence‐based, while others are more likely to have limited efficacy. The results of the present study are consistent with previous Pinterest research; however, more information is needed to best understand efficacy and implementation patterns. By looking into pin use, future researchers will determine how followers of NASP on Pinterest choose and implement pins, thus providing a means to leverage Pinterest for dissemination of evidence‐based content. 相似文献
12.
NomenclatureV-Relative velocity vectorV′-Absolute velocity vectorω-Relative vorticity vectorω′-Absolute vorticity vectorR-Pipe radiusa-Radius of cylinder for helical vortex filament2πl-Pitch of i mage helical vortex filamentQ-Flowrate in pipe with an arbitrary cross-sectionΓ-Circulation of each helical vortex filamentV0-Constant transferal velocity of vortex filaments along thez-axisΩ-Constant angular velocity of vortex filaments around thez-axis(a,χ1) ,(a,χ2) -Relative helical … 相似文献
13.
The structural and dielectric properties of Ba0.92Sr0.08Ti0.95Sn0.05O3 (BSTS) +x (molar ratio, %) Y3+ ceramics are investigated. Combining the lattice parameters and the distortion of crystal lattice, an alternation of substitution preference of Y3+ ion for the host cations in perovskite lattice is found. Owing to Y3+ ion entering the A site, the maximum dielectric constant is 5 627 for 1.25% Y3+-doped samples; when Y3+ ion is more than 1.25%, it tends to occupy the B site in perovskite lattice, causing a drop in the dielectric constant. Owing to the appearance of oxygen vacancy, the optimized dielectric loss is 0.004 for 1.25% Y3+-doped samples. The thermal stability of BSTS ceramics is significantly improved and the Curie temperature shifts to lower value with the amount of Y2O3 increased, making it a superior candidate for capacitor applications. 相似文献
14.
ＩＮＴＲＯＤＵＣＴＩＯＮＦｅｎｉｔｒｏｔｈｉｏｎ(0,0ｄｉｍｅｔｈｙｌ0(3ｍｅｔｈｙｌ4ｎｉｔｒｏｐｈｅｎｏｌ)ｐｈｏｓｐｈｏｒｏｔｈｉｏａｔｅ),ｔｈｅａｃｔｉｖｅｉｎｇｒｅｄｉｅｎｔｉｎｔｈｅｆｏｒｍｕｌａｔｅｄｐｒｏｄｕｃｔｓｕｍｉｔｈｉｏｎ,ｉｓａｎｏｒｇａｎｏｐｈｏｓｐｈａｔｅ(Ｏ-Ｐ)ｉｎｓｅｃｔｉｃｉｄｅａｎｄｕｓｅｄｉｎａｇｒｉｃｕｌｔｕｒｅｆｏｒｃｒｏｐｐｒｏｔｅｃｔｉｏｎａｎｄｃｏｎｔｒｏｌｏｆｖｅｃｔｏｒｂｏｒｎｄｉｓｅａｓｅｓｉｎｖａｒｉｏｕｓｃｏｕｎｔｒｉｅｓ(Ｓｅｌｆｅｔａｌ.,19… 相似文献
15.
为了解不同空调风机的内流机制,采用数值分析和PIV实验研究相结合的方法对空调用贯流风机和轴流风机内部复杂的旋涡流动现象进行了研究。结果表明:空调壁挂机用贯流风机内部偏心涡沿轴向具有明显的三维分布特性,偏心涡径向位置沿轴向几乎没有变化,其周向位置沿轴向不断改变。贯流风机偏心涡卷吸区域随负载提高而增强。高负载时,偏心涡更加靠近叶轮中心和蜗壳方向。空调室外机用开式斜流风轮的叶尖涡产生于距叶片前缘1/4区域,靠近吸力面。叶尖涡随风轮转速的提高而增强,并沿着与风轮旋向相反的方向朝下游发展。 相似文献
16.
A NEW APPROACH TO INCREASE THE ATTAINABLE RICE YIELD IN INTENSIVE IRRIGATED RICE SYSTEMS OF ZHEJIANG PROVINCE, CHINA 总被引：1，自引：0，他引：1
ＩＮＴＲＯＤＵＣＴＩＯＮＺｈｅｊｉａｎｇＰｒｏｖｉｎｃｅｌｏｃａｔｅｄｉｎｓｏｕｔｈｅａｓｔｅｒｎＣｈｉｎａｂｅｌｏｎｇｓｔｏｔｈｅｓｕｂｔｒｏｐｉｃａｌｃｌｉｍａｔｉｃｚｏｎｅｗｉｔｈｗａｒｍｔｅｍｐｅｒａｔｕｒｅ (ｍｅａｎｔｅｍｐｅｒａｔｕｒｅ 1 5-1 8℃ )ａｎｄａｄｅｑｕａｔｅｒａｉｎｆａｌｌ (ａｎｎｕａｌｐｒｅｃｉｐｉｔａ ｔｉｏｎ 1 1 0 0 -1 90 0ｍｍ) .Ｏｆｔｈｅｔｏｔａｌｏｆ1 .62ｍｉｌ ｌｉｏｎｈａｃｕｌｔｉｖａｔｅｄｌａｎｄｉｎｔｈｉｓｐｒｏｖｉｎｃｅ ,1 .2 7ｍｉｌｌｉｏｎｈａａｒｅｒ… 相似文献
17.
概要介绍了集中供热中传统流量计和涡街流量计的特点以及几种流量计在实际的应用情况,分析 了涡街流量计在集中供热的实际应用中的优势和问题,着重阐述了涡街流量计的集中管理. 相似文献
18.
对于p>0,Lutwak定义了凸体K的新几何体Γ_(-p)K的概念,本文建立了新几何体Γ_(-p)K和它的极体的几个不等式 相似文献
19.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｉｃｒｏｓｔｒｕｃｔｕｒｅｏｆｔｈｉｎｆｉｌｍｓｐｌａｙｓａｃｒｕ ｃｉａｌｒｏｌｅｉｎａｗｉｄｅｖａｒｉｅｔｙｏｆｐｈｙｓｉｃａｌｐｒｏｃｅｓｓｅｓ.Ｔｈｅｒｅａｒｅｃｌｅａｒｅｖｉｄｅｎｃｅｓｔｈａｔｍａｎｙｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆａｔｈｉｎｆｉｌｍｖａｒｙｄｒａｍａｔｉｃａｌｌｙａｓｉｔｓｍｉｃｒｏｓｔｒｕｃｔｕｒｅｃｈａｎｇｅｓ (Ｈａｕｓｅｔａｌ.,1 987) .Ｆｏｒｉｎｓｔａｎｃｅ,ｒｏｕｇｈｓｕｂｓｔｒａｔｅｓｃａｎｂｅｕｓｅｄｔｏｆａｂｒｉｃ… 相似文献
20.
Wang Guan Hao Mingyue Liu Qiong Jiang Yanlong Huang Haibin Yang Guilian Wang Chunfeng 《Journal of Zhejiang University. Science. B》2021,22(5):348-365
This study probed the protective effect of recombinant Lactobacillus plantarum against hydrogen peroxide(H_2O_2)-induced oxidative stress in human umbilical vein endothelial cells(HUVECs). We constructed a new functional L. plantarum(NC8-p SIP409-alr-angiotensin-converting enzyme inhibitory peptide(ACEIP)) with a double-gene-labeled non-resistant screen as an expression vector. A 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2 H-tetrazolium bromide(MTT) colorimetric assay was carried out to determine the cell viability of HUVEC cells following pretreatment with NC8-p SIP409-alr-ACEIP. Flow cytometry(FCM) was used to determine the apoptosis rate of HUVEC cells. Cysteinyl aspartate specific proteinase(caspase)-3/8/9 activity was also assayed and western blotting was used to determine protein expression of B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), inducible nitric oxide synthase(i NOS), nicotinamide adenine dinucleotide phosphate oxidase 2(gp91 phox), angiotensin II(Ang II), and angiotensin-converting enzyme 2(ACE2), as well as corresponding indicators of oxidative stress, such as reactive oxygen species(ROS), mitochondrial membrane potential(MMP), malondialdehyde(MDA),and superoxide dismutase(SOD). NC8-p SIP409-alr-ACEIP attenuated H_2O_2-induced cell death, as determined by the MTT assay. NC8-p SIP409-alr-ACEIP reduced apoptosis of HUVEC cells by FCM. In addition, compared to the positive control, the oxidative stress index of the H_2O_2-induced HUVEC(Hy-HUVEC), which was pretreated by NC8-p SIP409-alr-ACEIP, i NOS,gp91 phox, MDA, and ROS, was decreased obviously; SOD expression level was increased; caspase-3 or-9 was decreased, but caspase-8 did not change; Bcl-2/Bax ratio was increased; permeability changes of mitochondria were inhibited; and loss of transmembrane potential was prevented. Expression of the hypertension-related protein(Ang II protein) in HUVEC cells protected by NC8-p SIP409-alr-ACEIP decreased and expression of ACE2 protein increased. These plantarum results suggested that NC8-p SIP409-alr-ACEIP protects against H_2O_2-induced injury in HUVEC cells. The mechanism for this effect is related to enhancement of antioxidant capacity and apoptosis. 相似文献