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<i>L<sup>p</sup>p</i>-Harmonic 1-Forms on <i>δ</i>-Stable Hypersurface in Space Form with Nonnegative Bi-Ricci Curvature
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作者 Bakry Musa Jiancheng Liu 《Advances in Pure Mathematics》 2021年第5期427-439,共13页
In this paper, we investigate the space of <em>L<sup>p</sup> p</em>-harmonic 1-forms on a complete noncompact orientable <em>δ</em>-stable hypersurface <em>M<sup>m</... In this paper, we investigate the space of <em>L<sup>p</sup> p</em>-harmonic 1-forms on a complete noncompact orientable <em>δ</em>-stable hypersurface <em>M<sup>m</sup></em> that is immersed in space form <img src="Edit_6fbc11b9-ac23-40e2-b045-0fb25419337d.png" width="35" height="23" alt="" /> with nonnegative BiRic curvature. We prove the nonexistence of <em>L<sup>p</sup> p</em>-harmonic 1-forms on <em>M<sup>m</sup></em>. Moreover, we obtain some vanishing properties for this class of harmonic 1-forms. 展开更多
关键词 Lp p-Harmonic 1-Forms δ-Stable hypersurface BiRic Curvature Space Form
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S^4(1)中具有两个相等的非零常数主曲率的完备超曲面
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作者 马志圣 《四川师范大学学报(自然科学版)》 CAS CSCD 1991年第2期54-60,共7页
设 M 是连通的、可定向的、完备的3维 C~∞黎曼流形,C:M→S^4(1)是从 M 列4维单位球面 S^4(1)中的等距浸入.主曲率 h_1,h_2,h_3满足 h_1=h_2=R(常数).本文证明了:浸入或者是全脐的,或者是无脐点的;若浸入是全脐的.或无脐点且 h_3为常数,... 设 M 是连通的、可定向的、完备的3维 C~∞黎曼流形,C:M→S^4(1)是从 M 列4维单位球面 S^4(1)中的等距浸入.主曲率 h_1,h_2,h_3满足 h_1=h_2=R(常数).本文证明了:浸入或者是全脐的,或者是无脐点的;若浸入是全脐的.或无脐点且 h_3为常数,则 M 可完全确定:若 h_3不是常数,则 M 微分同胚于 E^4中环准超环面. 展开更多
关键词 4维单位球面 S^4(1) 完备超曲面主曲率 脐点 标准超环面
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Petrogenesis of Late Cretaceous Jiangla'angzong I-Type Granite in Central Lhasa Terrane, Tibet, China: Constraints from Whole-Rock Geochemistry, Zircon U-Pb Geochronology, and Sr-Nd-Pb-Hf Isotopes 被引量:26
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作者 LIU Hong LI Guangming +7 位作者 HUANG Hanxiao CAO Huawen YUAN Qian LI Yingxu OUYANG Yuan LAN Shuangshuang LU Menghong YAN Guoqiang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1396-1414,共19页
The Jiangla'angzong granite in the northern part of the Central Lhasa Terrane is composed of syenogranite and adamellite. LA-ICP-MS zircon U-Pb analyses suggest that syenogranite has a weighted mean 2±6pb/23SU a... The Jiangla'angzong granite in the northern part of the Central Lhasa Terrane is composed of syenogranite and adamellite. LA-ICP-MS zircon U-Pb analyses suggest that syenogranite has a weighted mean 2±6pb/23SU age of 86±1 Ma (mean square weighted deviation=0.37), which is in accordance with the muscovite Ar-Ar age (85±1 Ma) of Cu-Au ore-bearing skarns and the zircon U-Pb age (84±1 Ma) of adamellite. This suggests that the Jiangla'angzong magmatism and Cu-Au mineralization events took place during the Late Cretaceous. The granite contains hornblende, biotite, and pyroxene, and does not contain Al-bearing minerals, such as muscovite, cordierite, and garnet. It has high contents of SiO2 (65.10 -70.91wt%), K20 (3.44-5.17wt%), and total K20+Na20 (7.13-8.15wt%), and moderate contents of A12Oa (14.14-16.45wt%) and CaO (2.33-4.11wt%), with a Reitman index (δ43) of 2.18 to 2.33, and A/ CNK values of 0.88 to 1.02. The P205 contents show a negative correlation with SiO2, whereas Pb contents show a positive correlation with SiO2. Th and Y contents are relatively low and show a negative correlation with the Rb contents. These characteristics suggest that the Jiangla'angzong granite is a high K calc-alkaline metaluminous I-type granite. It is enriched in light rare earth elements (LREE) and large ion lithofile elements (LILE), and depleted in heavy rare earth elements (HREE) and high field strength elements (HFSE), with LREE/HREE ratios of 11.7 to 18.1. The granite has negative Eu anomalies of 0.58 to 0.94 without obvious Ce anomalies (δCe=l.00-1.04). The relatively low initial a7Sr/a6Sr ratios of 0.7106 to 0.7179, positive ε±nt(t) values of 1.0 to 4.1, and two-stage Hf model ages (TDM2) ranging from 889 Ma to 1082 Ma, These geochemical features indicate that the granite derived from a juvenile crust. The (143Nd/144Nd)t values from the Jiangla'angzong granite range from 0.5121 to 0.5123, its eNd(t) values range from -10.17 to -6.10, its (^206pb /^204pb)t values range from 18.683 to 18.746, its (^207pb /^204pb)t values range from 15.695 to 15.700, and its (^208pb /^204pb)t values range from 39.012 to 39.071. These data indicate that the granite was formed by melting of the upper crust with the addition of some mantle materials. We propose that the Jiangla'angzong granite was formed during the post- collision extension of the Qiangtang and Lhasa terranes. 展开更多
关键词 Bangong Co-Nujiang Jiangla'angzong 1-type granite Zircon U-Pb Sr-Nd-Pb-Hf
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球空间中极小超曲面上L^(p)调和1-形式的有限性定理
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作者 姚中伟 《西南师范大学学报(自然科学版)》 CAS 2023年第3期39-46,共8页
设M^(m)(m≥3)是空间S^(m+1)中的完备定向非紧极小超曲面,考虑子流M^(m)上L^(p)调和1-形式的有限性问题.如果极小超曲面M^(m)存在一个紧致子集Ω使得MΩ是稳定的,则称M^(m)具有有限的指数.首先,在M^(m)有有限指数的假设条件下,应用Boch... 设M^(m)(m≥3)是空间S^(m+1)中的完备定向非紧极小超曲面,考虑子流M^(m)上L^(p)调和1-形式的有限性问题.如果极小超曲面M^(m)存在一个紧致子集Ω使得MΩ是稳定的,则称M^(m)具有有限的指数.首先,在M^(m)有有限指数的假设条件下,应用Bochner公式、Sobolev不等式及截断函数和指标迭代的方法,证得:如果2≤p≤2m/m-1,则M^(m)上L^(p)调和1-形式空间的维数有限.其次,记A为超曲面M^(m)的第二基本形式,M^(m)的全曲率定义为第二基本形式的L2模.在M^(m)全曲率有正上界的假设条件下(特别地,该正上界的取值仅依赖于子流形M^(m)的维数m),利用截断函数法,得到了M^(m)上L^(p)调和1-形式的有限性定理.特别地,令p=2,可进一步得到,在极小超曲面M^(m)具有有限指数或全曲率有正上界的假设条件下,M^(m)仅有有限多个非抛物端. 展开更多
关键词 L^(p)调和1-形式 极小超曲面 有限指数 有限性定理
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N维欧氏空间R^n上2次n-1维流形及性质 被引量:1
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作者 李天平 席小忠 《赣南师范学院学报》 2000年第3期12-14,共3页
本文讨论了N维欧氏空间Rn 上 2次n - 1维流形的若干性质 ,得到了n - 1维超球面、n - 1维超椭球面、n - 1维超双曲面几个典型的n -
关键词 n-1维流形 欧氏空间 超球面 N维 超双曲面
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4维de Sitter空间中有限型旋转曲面 被引量:2
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作者 黄安民 徐平 邹业兵 《江西师范大学学报(自然科学版)》 CAS 1999年第1期70-74,共5页
研究E51中4维deSiter空间S41的坐标函数是其Laplace的特征函数的球型和双曲型旋转曲面M的性质,得到M是S41的极大或极小超曲面,或者当M是球型旋转曲面,M可与S2(a)×S11(1-a2)或S2(... 研究E51中4维deSiter空间S41的坐标函数是其Laplace的特征函数的球型和双曲型旋转曲面M的性质,得到M是S41的极大或极小超曲面,或者当M是球型旋转曲面,M可与S2(a)×S11(1-a2)或S2(a)×H1(a2-1)叠合,当M是双曲型旋转曲面。 展开更多
关键词 SITTER空间 有限型 旋转曲面 极小曲面 极大曲面
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关于《2型球面超曲面》一文的注记
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作者 赵培标 宋鸿藻 吴炳烨 《应用数学》 CSCD 1998年第2期128-130,共3页
本文证明了2型球面紧致超曲面是1型的,因而是质量对称的.换言之,不存在2型球面紧致超曲面,推广了文[2,3,4,5」中的结论.
关键词 2型超曲面 质量对称 常平均曲率 超曲面 球面
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Two Types of Granites in the Western Yangtze Block and Their Implications for Regional Tectonic Evolution: Constraints from Geochemistry and Isotopic Data 被引量:5
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作者 MABI Awei YANG Zhengxi +3 位作者 ZHANG Mingchun WEN Dengkui LI Yanlong LIU Xuyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期89-105,共17页
In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and tectonic setting... In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and tectonic setting are still controversial. In this paper, zircon U-Pb ages, Sm-Nd isotopic and whole-rock geochemical data are reported from selected fresh samples in the southern Dechang county, southwestern China, in order to constrain their emplacement age and magma source, as well as their petrogenesis and tectonic setting. They are mainly composed of biotite monzogranite, monzonitic granite, biotite granodiorites, and quartz diorite. Two ages of 1055 ± 43 Ma and 837.6 ± 3.8 Ma were obtained through zircon U-Pb dating by LA-ICP-MS and LA-MC-ICP-MS, respectively. According to their major element compositions, the Grenville-age granites are peraluminous calc-alkaline series calcic S-type granite. In contrast, the mid-Neoproterozoic granites are metaluminous calc-aikaline series alkalic I-type granite. Furthermore, the S-type granites are enriched in LREEs relative to HREEs with (La/Yb)N ratios of 3.85-18.56 and underwent major fractionation with strongly negative Eu anomalies (Eu/Eu* = 0.38-0.66). In the MORB-normalized trace element variation diagram, all the samples are enriched in Ce and large ion lithophile elements such as Rb, Th, and K, and depleted in high field strength elements such as Nb, and Ti, with negative Sr and Ti anomalies. The I-type granites are enriched in LREEs with slight negative Eu anomalies (Eu/Eu*= 0.83-0.93). They are characterized by the enrichment of highly incompatible elements (such as K, Rb, Ba, Th) and LREEs, relative to MORB. Neodymium isotopic data show that the S-type granites display 143Nd/144Nd values of 0.51241-0.51256, and have eNa (t = 1055 Ma) values of (-3.29) to (-3.81). Calculated tDM ages yield values from 1.87 to 1.91 Ga with the tDM.2stg ages of 1.86 to 1.9 Ga. The I-type granites have 143Nd/144Nd ratios between 0.51192 and 0.51195, corresponding to initial eNd (t = 837 Ma) values of 1.22 to 5.63. Calculated tDM ages yield values from 1.0 to 1.38 Ga and the tDM.2stg ages yield values from 0.99 to 1.06 Ga. The S-type granites are distinguished as syn-collision granite, whereas the I-type granites were formed as arc magmas according to the Rb-(Yb+Ta) and R1-R2 tectonic discrimination diagrams. To conclude, there are two types of spatially associated granite, the Mesoproterozoic S-type granite which were derived from re- melting of upper crustal mudstone and/or clastics and resulted from the convergence of two continental plates, and the mid-Neoproterozoic I-type granite which formed in continental arc and resulted from mantle-derived magma mixed crust material, in the western Yangtze Block. Furthermore, we suggest that collision between the Yangtze and Cathaysia blocks occurred at about 1055 Ma, and caused the S- type granite. The I-type granite related to the subduction of oceanic lithosphere eastward underneath the Yangtze Block in the mid-Neoproterozoic. 展开更多
关键词 1-type granite S-type granite GEOCHEMISTRY PETROGENESIS tectonic setting Western YangtzeBlock
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Effect of Chinese Herbal Treatment on Th1- and Th2-Type Cytokines,Progesterone andβ-Human Chorionic Gonadotropin in Early Pregnant Women of Threatened Abortion 被引量:18
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作者 刘芳 罗颂平 《Chinese Journal of Integrative Medicine》 SCIE CAS 2009年第5期353-358,共6页
Objective: To study the clinical effects of Prescription Zhuyun-Ⅲ (助孕3号方, ZYⅢ) on early pregnant women diagnosed as threatened abortion, and its mechanism in immunity and endocrine by determining serum Th1- a... Objective: To study the clinical effects of Prescription Zhuyun-Ⅲ (助孕3号方, ZYⅢ) on early pregnant women diagnosed as threatened abortion, and its mechanism in immunity and endocrine by determining serum Th1- and Th2-type cytokines, progesterone, and β-human chorionic gonadotropin (β-HCG). Methods: The treatment group comprised 30 early pregnant women diagnosed as threatened abortion of deficiency syndrome of Pi (脾), Shen (肾), or both. The control group consisted of 20 normal early pregnant women of similar gestational age. Patients in the treatment group were administered with ZYⅢ for 4 weeks. Peripheral blood samples were collected pre- and post-treatment from both the treatment and the control groups. Serum Thl-type cytokine [interleukin-2 (IL-2)] and Th2-type cytokine [interleukin-10 (IL-10)] were determined by flow cytometry, and serum progesterone and 13-HCG were determined by ELISA. Results: (1) The treatment was effective in 26 and ineffective in 4 patients of the treatment group. Therefore, the cure percentage was 86.67%. (2) In the treatment group before the treatment, IL-2 was significantly higher, IL-10 tended to be less, and the Th1/Th2 balance shifted toward Thl compared with those in the control group. (3) After the treatment, IL-2 was decreased, IL-10 was increased, and IL-2/IL-10 was decreased. Both progesterone and β-HCG were increased. Changes of progesterone were positively correlated with changes of IL-10, whereas changes of β-HCG were negatively correlated with changes of IL-2. Conclusions: Our study suggests that ZYⅢ has an evident function of protecting the fetus, and one of its mechanisms is inhibiting the secretion of Thl cytokines, promoting the secretion of Th2 cytokines, and recovering the pathological shift of the Th1/Th2 balance. The other possible mechanism is increasing serum progesterone and β-HCG concentrations. Moreover, there are some correlations between the above two effects. 展开更多
关键词 threatened abortion Prescription Zhuyun-Ⅲ Th1- and Th2-type cytokines PROGESTERONE β-human chorionic gonadotropin
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Petrogenesis of Kejie Granite in the Northern Changning-Menglian Zone, Western Yunnan: Constraints from Zircon U-Pb Geochronology, Geochemistry and Hf Isotope 被引量:3
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作者 NIE Fei DONG Guochen +4 位作者 MO Xuanxue WANG Xia FAN Wenyu DONG Meiling ZHU Huaping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第3期754-765,共12页
The Kejie pluton is located in the north of the Changning-Menglian suture zone. The rock types are mainly biotite-granite. Zircon LA-ICP-MS U-Pb dating indicates that the Kejie pluton emplaced at about 80-77 Ma, Late ... The Kejie pluton is located in the north of the Changning-Menglian suture zone. The rock types are mainly biotite-granite. Zircon LA-ICP-MS U-Pb dating indicates that the Kejie pluton emplaced at about 80-77 Ma, Late Cretaceous. The Kejie pluton samples are characterized by high SiO2 (71.68%-72.47%), K2O (4.73%-5.54%), total alkali (K2O + Na2O = 8.21%-8.53%), K2O/Na2O ratios (1.36-1.94) and low P2O5 (0.13%-0.17%), with A/CNK of 1.025-1.055; enriched in U, Th, and K, depleted in Ba, Nb, St, Ti, P and Eu. They are highly fractionated, slightly peraluminous 1-type granite. The two samples of the Kejie pluton give a large variation of εHf(t) values (-5.04 to 1.96) and Hf isotope crustal model ages of 1.16-1.5 Ga. Zircon Hf isotopes and zircon saturation temperatures of whole-rock (801℃-823℃) show that the mantle-derived materials maybe have played a vital role in the generation of the Kejie pluton. The Kejie pluton was most likely generated in a setting associated with the eastward subduction of the neo-Tethys ocean, where intrusion of mantle wedge basaltic magmas in the crust caused the anatexis of the latter, forming hybrid melts, which subsequently experienced high-degree fractional crystallization. 展开更多
关键词 Zircon U-Pb dating and Hf isotope GEOCHEMISTRY highly fractionated 1-type granite Kejiepluton neo-Tethys ocean
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Geochronology and Sr-Nd-Hf isotopic composition of the granites,enclaves,and dikes in the Karamay area,NW China:Insights into late Carboniferous crustal growth of West Junggar 被引量:8
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作者 Di Li Dengfa He Chun Fan 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第2期153-173,共21页
New whole-rock major and trace elements, and zircon U Pb and Hf-Nd isotope compositions are reported for the Karamay dikes, enclaves, and host granites in the West Junggar, NW China. Zircon U -Pb dating of the l(aram... New whole-rock major and trace elements, and zircon U Pb and Hf-Nd isotope compositions are reported for the Karamay dikes, enclaves, and host granites in the West Junggar, NW China. Zircon U -Pb dating of the l(aramay pluton yields an age of 300.7 ~ 2.3 Ma for the enclave and 300.0 ~ 2.6 Ma for the host granite, which was intruded by dike with an age of 298 Ma. The host granites exhibit relatively low SiO2 contents and A/CNK and Ga/Al ratios, low initial 87Sr/86Sr ratios (0.703421 0.703526) and positive eHf(t) (5.5--14.1) and eNd(t) (7.3--8.1) values with a young model age, suggesting that they are I-type granites and were mainly derived from a juvenile lower crustal source. The enclaves and dikes belong to an andesitic calc-alkaline series and have high MgO concentrations at low silica content and positive eHf(t) (7.6--13.2, 14.2--14.9) and εNd(t) (6.8-8.3, ~6.9) values. They are enriched in LILEs (Rb, Ba and U) and LREE and depleted in HFSEs (Nb and Ta) with insignificant negative Eu anomalies, indicating that the melts were derived from an enriched lithospheric mantle modified by subducted oceanic crust-derived melts and minor fluids, followed by fractional crystallization. The Karamay host granites and enclaves are of mixed origin and are most probably formed by the interaction between the lower crust-and lithospheric mantle-derived magmas, and were intruded by the unmixed dikes subsequently. The upwelling mantle through a slab window in an island arc environment might have triggered partial melting of the lithospheric mantle and its subsequent interaction with the granitic magma, further suggesting that the ridge subduction played an important role in the crustal growth of West lun^gar. 展开更多
关键词 1-type graniteEnclaveDikeSr-Hf-Nd isotopic compositionsMagma mixingKaramay intrusions
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Deviation matrix and asymptotic variance for GI/M/1-type Markov chains 被引量:3
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作者 Yuanyuan LIU Pengfei WANG Yanmin XIE 《Frontiers of Mathematics in China》 SCIE CSCD 2014年第4期863-880,共18页
We investigate deviation matrix for discrete-time GI/M/1-type Markov chains in terms of the matrix-analytic method, and revisit the link between deviation matrix and the asymptotic variance. Parallel results are obtai... We investigate deviation matrix for discrete-time GI/M/1-type Markov chains in terms of the matrix-analytic method, and revisit the link between deviation matrix and the asymptotic variance. Parallel results are obtained for continuous-time GI/M/1-type Markov chains based on the technique of uniformization. We conclude with A. B. Clarke's tandem queue as an illustrative example, and compute the asymptotic variance for the queue length for this model. 展开更多
关键词 GI/M/1-type Markov chains deviation matrix asymptoticvariance matrix-analytic method
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PROXIMINAL SUBSPACES OF 2-NORMED SPACES 被引量:1
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作者 Sh.Rezapour 《Analysis in Theory and Applications》 2006年第2期114-119,共6页
In 1965 Gohler introduced 2-normed spaces and since then, this topic have been intensively studied and developed. We shall introduce the notion of 1-type proximinal subspaces of 2-normed spaces and give some results i... In 1965 Gohler introduced 2-normed spaces and since then, this topic have been intensively studied and developed. We shall introduce the notion of 1-type proximinal subspaces of 2-normed spaces and give some results in this field. 展开更多
关键词 b-proximinal subspaces 1-type proximinal subspaces 2-functionals
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Inactivated Pseudomonas PE(△Ⅲ)exotoxin fused to neutralizing epitopes of PEDV S proteins produces a specific immune response in mice 被引量:1
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作者 Leqiang Sun Yajie Tang +2 位作者 Keji Yan Huanchun Chen Huawei Zhang 《Animal Diseases》 2021年第3期205-211,共7页
Porcine epidemic diarrhea(PED)caused by the porcine epidemic diarrhea virus(PEDV),is a severe infectious and devastating swine disease that leads to serious economic losses in the swine industry worldwide.An increased... Porcine epidemic diarrhea(PED)caused by the porcine epidemic diarrhea virus(PEDV),is a severe infectious and devastating swine disease that leads to serious economic losses in the swine industry worldwide.An increased number of PED cases caused by variant PEDV have been reported in many countries since 2010.S protein is the main immunogenic protein containing some B-cell epitopes that can induce neutralizing antibodies of PEDV.In this study,the construction,expression and purification of Pseudomonas aeruginosa exotoxin A(PE)without domain Ⅲ(PE△Ⅲ)as a vector was performed for the delivery of PEDV S-A or S-B.PE(△Ⅲ)PEDV S-A and PE(△Ⅲ)PEDV S-B recombinant proteins were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis.The immunogenicity of PEDV S-A and PEDV S-B subunit vaccines were evaluated in mice.The results showed that PEDV-S-B vaccine could not only induce specific humoral and Th1 type-dominant cellular immune responses,but also stimulate PEDV-specific mucosal immune responses in mice.PEDV-S-B subunit vaccine is a novel candidate mucosal vaccine against PEDV infection. 展开更多
关键词 Porcine epidemic diarrhea virus S protein Neutralizing antibody Th1-type immune response
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Environment-assisted excitation energy transfer in LH1-RC-type and LH2-type trimers
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作者 TAN QingShou KUANG LeMan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第9期1541-1548,共8页
In this work,we study environment-assisted excitation energy transfer(EET) through calculating energy transfer efficiency(ETE) in LH1-RC-type and LH2-type trimers,which can be used to mimic energy transfer behaviors i... In this work,we study environment-assisted excitation energy transfer(EET) through calculating energy transfer efficiency(ETE) in LH1-RC-type and LH2-type trimers,which can be used to mimic energy transfer behaviors in the basic unit cells of LH1-RC and LH2 light-harvesting complexes.Quantum state evolution of the trimers is described by a non-Hermitian quantum master equation.ETE in these trimer systems is investigated by the use of numerical solutions at finite temperatures for the non-Hermitian master equation.We theoretically reveal the temperature-assisted ETE enhancement.It is found that highly efficient EET with nearly unit efficiency may occur in the nearby regime of the critical point of quantum phase transition. 展开更多
关键词 excitation energy transfer LH1-RC-type and LH2-type trimers quantum phase transition
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Petrogenesis of the Mayo-Darley tin formations,anorogenic complex of the Cameroon Line:implication for tin deposit
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作者 Ndema Mbongué Jean Lavenir Ndongfong Edson Fuh Emmanuel Eseya Mengu Junior 《Acta Geochimica》 EI CAS CSCD 2023年第4期704-725,共22页
The Mayo-Darley massif is an anorogenic complex of the Cameroon Line that has a mantle origin.Tin-bearing rocks were analyzed by ICP-AES and INAA analytical methods.The purpose of this work was to provide new geochemi... The Mayo-Darley massif is an anorogenic complex of the Cameroon Line that has a mantle origin.Tin-bearing rocks were analyzed by ICP-AES and INAA analytical methods.The purpose of this work was to provide new geochemical data for the Mayo-Darley tin formation and to understand its petrogenesis and the origin of tin mineralization.The Mayo-Darley tin deposit is made up of tin-granite,and tin-greisen,greisenification was developed on the borders of quartz dykes.These rocks belong to the alkaline series and were classified into acid(SiO2-=61.6%–73.8%;65.4%–98%respectively)and basic(42.9%–47%SiO_(2))rocks.They showed enrichment in HSFE,LILE,Ga/Al and chondrite normalized REE patterns indicating LREE enrichment relative to HREE with a negative Eu anomaly,only sample SB8 of tin-granite showed Eu/Eu*=1.11.Rocks display metaluminous,peralkaline,peraluminous,ferroan,high-K calc-alkaline to shoshonitic,alkalic to calcic affinity,and crystallized at800°C.The chemistry of this deposit reflects the primary composition of granite,quartz monzonite,gabbro,and foid gabbro.This complex experienced multi-stage sub-solidus hydrothermal fluid reactions and shows variable alteration of feldspars alkali mobility.The rocks are classified as A1-type granite,overlap with the OIB field,and were derived from a within-plate setting,similar to mantle non plumederived magmas.The origin of tin mineralization in MayoDarley has a complex evolution,tin mineralization was derived from hydrothermal and hydrogenous metal-rich deposits and shows Sn–Hf–Zr and Sn–Tl–Nb association.These new data confirm the complexity of the Mayo-Darley tin complex and elucidate the origin of tin mineralization. 展开更多
关键词 Mayo-Darley MASSIF Cameroon Line Tingranite Tin-bearing GREISEN A1-type granite Sn–Hf–Zr Sn–Tl–Nb
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F-doped O3-NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_2 as high-performance cathode materials for sodium-ion batteries 被引量:5
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作者 Qin Zhang Yangyang Huang +6 位作者 Yi Liu Shixiong Sun Kun Wang Yuyu Li Xiang Li Jiantao Han Yunhui Huang 《Science China Materials》 SCIE EI CSCD 2017年第7期629-636,共8页
The F-doped O3-type NaNi1/3Fe1/3Mn1/3O2-xFx (x = 0, 0.005, 0.01,002 and noted as NFM-F0, NFM-F0.005, NFM-F0.01, NFM-F0.02, respectively, united as NFM-Fs) cathode materials were investigated systematically. The rate... The F-doped O3-type NaNi1/3Fe1/3Mn1/3O2-xFx (x = 0, 0.005, 0.01,002 and noted as NFM-F0, NFM-F0.005, NFM-F0.01, NFM-F0.02, respectively, united as NFM-Fs) cathode materials were investigated systematically. The rate performance and capacity retention of the O3-type cathode materials are significantly improved as a function of specific F-doping levels. Optimum performance is achieved in the NFM-F0.01 material having a capacity of -110mAhg-1 at a current density of 150mAg-1 after 70 cycles. The results indicate that the binding energy of oxygen changes as a result of F-doping, and in addition, F-doping results in changes to the stoichiometry of Mn3+/Mn4+, which stabilizes the O3-type layered structure, thus allowing cycling performance to be improved. However, NFM-F0.02, having a higher F-doping level, retains a high capacity retention, although a slight loss is observed. The results suggest there is an optimum F-doping level for the NFM-F system to deliver enhanced cycling performance. 展开更多
关键词 O3-type NaNi1/3Fe1/3Mn1/3O2 F-doping sodium-ionbatteries
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Boundedness of Commutators of θ-Type Calderón-Zygmund Operators on Non-homogeneous Metric Measure Spaces 被引量:1
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作者 Chol RI Zhenqiu ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2019年第4期585-598,共14页
Let(X, d, μ) be a metric measure space satisfying both the upper doubling and the geometrically doubling conditions in the sense of Hyt?nen. In this paper, the authors obtain the boundedness of the commutators of θ-... Let(X, d, μ) be a metric measure space satisfying both the upper doubling and the geometrically doubling conditions in the sense of Hyt?nen. In this paper, the authors obtain the boundedness of the commutators of θ-type Calderón-Zygmund operators with RBMO functions from L∞(μ) into RBMO(μ) and from Hat1,∞(μ) into L1(μ), respectively.As a consequence of these results, they establish the Lp(μ) boundedness of the commutators on the non-homogeneous metric spaces. 展开更多
关键词 NON-HOMOGENEOUS SPACE θ-type Calderón-Zygmund operator COMMUTATOR RBMO(μ) SPACE Hat1 ∞(μ) SPACE
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Micron-scale 1:5H-based precipitated phase with the lamellar structure of sintered Sm_(2)Co_(17)-based magnets and its potential application 被引量:2
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作者 Nengjun Yu Yingchang Li +6 位作者 Zesong Ren Minxiang Pan Hangfu Yang Qiong Wu Hongliang Ge Minggang Zhu Wei Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第22期159-165,共7页
The excellent thermal stability of magnetic properties of Sm_(2)Co_(17)-based magnets is their most impor-tant feature.However,this stability is reduced when the maximum energy product of Sm_(2)Co_(17)-based magnets i... The excellent thermal stability of magnetic properties of Sm_(2)Co_(17)-based magnets is their most impor-tant feature.However,this stability is reduced when the maximum energy product of Sm_(2)Co_(17)-based magnets is improved,which is mainly determined by the Fe/Cu distribution of the 2:17R cell and 1:5H cell boundary phases.During the demagnetization process,the Cu-rich 1:5H cell boundary phase with a width of 2-15 nm obstructs the motion of the domain walls,yielding coercivity.Herein,we report a micron-scale Cu/Zr-rich and Fe-lean 1:5H-based precipitated phase with a lamellar structure,probably induced by Sm_(2)O_(3) doping.This structure enables the separate regulation of Fe and Cu distribution for Sm_(2)Co_(17)-based magnets with Fe-rich 2:17R cell phases and Cu-rich 1:5H cell boundary phases,consid-erably optimizing the thermal stability of magnetic properties.This discovery can be further developed to produce Sm_(2)Co_(17)-based magnets with high performance and excellent thermal stability of magnetic properties. 展开更多
关键词 Sm_(2)Co_(17)-type magnets Thermal stability of magnetic properties 1:5H-based precipitated phase Element distribution
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Θ-type Calderón-Zygmund Operators with Non-doubling Measures 被引量:2
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作者 Ru-long XIE Li-sheng SHU 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2013年第2期263-280,共18页
Let μ be a Radon measure on Rd which may be non-doubling. The only condition that μ must satisfy is μ(B(x,r)) ≤ Urn for all x∈Rd, r 〉 0 and for some fixed 0 〈 n 〈 d. In this paper, under this assumption, w... Let μ be a Radon measure on Rd which may be non-doubling. The only condition that μ must satisfy is μ(B(x,r)) ≤ Urn for all x∈Rd, r 〉 0 and for some fixed 0 〈 n 〈 d. In this paper, under this assumption, we prove that 0-type Calder6n-Zygmund operator which is bounded on L2 (μ) is also bounded from L^∞(μ) into RBMO (μ) and from Hb (μ) into L1(μ). According to the interpolation theorem introduced by Tolsa, the LP(μ)-boundedness (1 〈 p 〈 ∞) is established for θ-type Calder6n-Zygmund operators. Via a sharp maximal operator, it is shown that commutators and multilinear commutators of θ-type CMderθn-Zygmundoperator with RBMO (μ) function are bounded on LP(μ) (1 〈 p 〈 ∞). 展开更多
关键词 non-doubling measure θ-type Calderón-Zygmund operator commutators multilinear commuta-tors RBMO ( μ ) space H1 ∞atb ( μ ) space
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