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带可更换梁段的钢框架端板式梁柱节点（RSFEBJ）是一种地震失效后可更换和修复的新型节点，该RSFEBJ与柱和梁端均采用端板式连接。通过组件法来研究RSFEBJ的初始转动刚度，综合考虑了柱腹板拉、压、剪变形及翼缘弯曲变形、梁柱端板受弯变形、连接端板（1、2）拉压及弯曲变形、梁腹板受剪及螺栓受拉变形对其的影响，建立了简化的弹簧模型，并在此基础上提出各组件的刚度计算公式。通过与课题组已开展的不同削弱形式下的RSFEBJ抗震性能有限元分析结果对比，理论值与有限元值之比均值为0.98，标准差为0.07，二者最大误差小于15%，表明公式具有较好的计算精度。最后开展了节点初始转动刚度的影响因素分析，结论表明：增大梁柱和连接端板厚度是提高节点初始转动刚度的有效手段。

为研究曲线CHS主钢管X形节点平面内受弯性能,建立了节点数值分析模型。首先,通过与轴压试验结果对比,验证了所建模型的准确性。进而分析主管曲直径比α、腹主管直径比β、主管径厚比γ对节点平面受弯性能的影响,并将有限元所得节点抗弯承载力与国外规范结果的比值Muf/Mu1、Muf/Mu2、Muf/Mu3进行对比分析。结果表明:当α≤12时,节点抗弯承载力随α增大而降低;而当α>12时,节点抗弯承载力基本不变。随β值增大,节点抗弯承载力增大;随γ值减小,节点抗弯承载力增大。美国规范未考虑γ的影响;日本规范所得Muf/Mu3值较大,偏安全;欧洲规范Muf/Mu2更趋近于1.0。最后选定欧洲规范公式作为抗弯承载力的基准公式,基于有限元结果对公式修正,最终得到CHS主钢管X形节点平面内抗弯极限承载力修正设计公式,供工程设计参考。

钢板深梁填充钢框架体系是一种新型的抗侧力结构体系,钢板深梁通过改变跨高比等参数不仅可以实现结构初始刚度能够在一定范围内调幅,而且使抗侧构件更容易安装或拆卸。以两侧加劲钢板深梁为研究对象,对其弹性屈曲性能进行了有限元分析,讨论不同加劲刚度对不同跨高比钢板深梁的加劲效果,并提出不同跨高比钢板深梁在加劲约束作用下的等效屈曲系数和嵌固系数。结果表明,跨高比越大,等效屈曲系数越小,实现屈曲模态转变所需加劲刚度越大,加劲效果越好。求得在屈曲模态转变点时,不同跨高比两侧加劲钢板深梁的加劲抗弯刚度比。提出对于跨高比在区间[0.5,1.0]的两侧加劲钢板深梁,嵌固系数可取1.23;对于跨高比在区间[1.0,2.0]时,嵌固系数取为1.0。分析结果为此类结构的抗侧设计提供了理论基础。

运用Ritz能量变分法推导出钢板深梁在水平荷载作用下的临界荷载计算公式。应用有限元软件ANSYS分析了钢板深梁的弹性屈曲机理,提出了3类典型屈曲模式,得到了钢板深梁在各类屈曲模式下的跨高比阈值。对跨高比为2.0的钢板深梁填充钢框架体系进行了试验研究。将得到的结果进行对比分析,结论如下:有限元所得第1类屈曲模态与试验屈曲模态一致;试验所得临界荷载与理论解误差为7.8%20.4%;理论结果与有限元所得第1类屈曲临界荷载接近,验证了理论解的正确性。所得结果可为此类构件的设计和应用提供理论基础。

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To evaluate the clinical effects of percutaneous balloon compression (PBC) of the Gasserian ganglion for primary trigeminal neuralgia. Methods The clinical data of 2 089 patients with primary trigeminal neuralgia treated with PBC in Hangzhou First People’s Hospital from January 2010 to January 2020 were analyzed retrospectively, and the relevant literature was reviewed. Results 1 998 cases (95.6%) were effective immediately after operation, including 1 944 (93.1%) of facial numbness, 1 036 (49.6%) of masticatory muscle weakness, 624 (29.9%) of perioral herpes, and 3 (0.1%) of diplopia. There was no difference in efficacy between elderly patients and non-elderly patients. No serious complications such as intracranial hemorrhage and death occurred. During follow-up, 349 cases (16.7%) recurred. Conclusion PBC is a very safe and effective minimally invasive method for the treatment of primary trigeminal neuralgia, especially for elderly patients, who can not tolerate craniotomy and recurrence after MVD. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, the fabrication of nanoparticles (NPs) with exact one functional group on the surface was reported. Mono-functional NPs were prepared by solid phase synthesis based on the strict sparse modification of silica sphere substrate. Four-arm dendrimer-like polystyrene (FDP) was employed to grafted onto the surface of the silica spheres and occupy a certain area on the surface, the FDP was confirmed to distribute independently on the surface by TEM. As a result, the thiol groups exposed at the graft point on the surface of silica sphere were strictly sparsely distributed after dissociating the polystyrene arms of the FDP. One-by-one attachment of AuNPs sized smaller than the diameter of the FDP and then cleaved the linker between silica sphere and AuNPs endowed the AuNPs with exact one reactive group. Mono-valence of the AuNPs were confirmed by dimerization between them. A high yield of AuNPs dimers demonstrated the relatively high reactivity of the surface functional group. The mono-functional AuNPs are strong candidates for constructing nanoparticle assemblies with controlled. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Changzhou University (Natural Science Edition) / Changzhou Daxue Xuebao (Ziran Kexue Ban) is the property of Editorial Department of Journal of Changzhou University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to further understand the rheological mechanics behavior of hard brittle rock under the condition of unloading, a unloading rheological test was made on the hard brittle granite by using rock automatic triaxial servo rheometer to investigate its creep laws and creep properties. Also, the method of determining the long-term strength of hard brittle rock was analyzed according to the test results. The results show that the rheological behavior of hard brittle rock under unloading path is different from that of loading path, and the lateral creep behavior is more likely to happen than the axial creep behavior; the higher the deviatoric stress level, the greater the steady-state creep rate, and they show the relationship of exponential function; the rock enters the stage of accelerated creep when its stress level exceeds the rheological threshold, and fails rapidly with its ductile dilatancy. According to the experimental results, the long-term strength of rock creep should be determined by the point of intersection of creep rate in both axial and lateral at the steady-state creep stage. The long-term strength determined by the method can increase the reliability by 10% than that using the traditional methods. [ABSTRACT FROM AUTHOR]