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A peculiar composite M-and W-type REE tetrad effect:Evidence from the Shuiquangou alkaline syenite complex,Hebei Province,China

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Chinese Science Bulletin 2010年第24期55卷 2684-2696页

作者： zhao ZhenHua bao ZhiWei QIAO YuLou Key Laboratory for Metallogenic Dynamics Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

A new type of REE tetrad effect,a composite M-and W-type,was recognized in the K-feldsparthized and silicificated Shuiquangou alkaline syenites,Dongping,Hebei *** analytical methods such as ICP-MS and isotopic dilution thermal ion mass spectrometer were exploited to verify the REE concentrations of the samples in three laboratories in China,France and *** results are reliable and consistent within *** situ quantitative analysis of REE concentrations of individual zircons and apatites extracted from the very same sample has shown that fractional crystallization of magma and the superimposed hydrothermal alteration might have taken place in at least two-stage hydrothermal activities to generate the composite M-and W-type REE tetrad *** coexisting melt and aqueous phases,the superimposed alteration by volatile(Cl,CO2) -and Si,K, Al-enriched high temperature hydrothermal fluids might be the important facts for this new MW-type of REE tetrad *** addition,the peculiar MW-type tetrad effect might be an indicator for Au mineralization of reworked plutons.

关键词：四重效应碱性正长岩水泉沟河北省稀土 W型复合中国

Influence of particle packing structure on sound velocity

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Chinese Physics B 2018年第10期27卷 386-394页

作者： Chuang zhao Cheng-Bo Li Lin bao College of Physics Guizhou UniversityGuiyang 550025China College of Mathematics and Physics Anyang Institute of TechnologyAnyang 455000China

The anisotropy in the particle systems of different packing structures affects the sound velocity. The acoustic propagation process in four kinds of packing structures（denoted as S45, H60, S90, and D） of two-dimensional granular system is simulated by the discrete element method. The velocity vtof obtained by the time of flight method and the velocity vc obtained from the stiffness tensor of the system are compared. Different sound velocities reflect various packing structures and force distributions within the system. The compression wave velocities of H60 and S90 are nearly the same, and transmit faster than that of D packing structure, while the sound velocity of S45 is the smallest. The shear wave velocities of S45 and H60 are nearly the same, and transmit faster than that of D packing structure. The compression wave velocity is sensitive to the volume fraction of the structure, however, the shear wave velocity is more sensitive to the geometrical structure itself. As the normal stress p is larger than 1 MPa, vtof and vc are almost equal, and the stiffness tensors of various structures explain the difference of sound velocities. When the normal stress is less than 1 MPa, with the coordination number unchanged, the law vtof ∝ p^1/4 still exists. This demonstrates that apart from different power laws between force and deformation as well as the change of the coordination number under different stresses, there are other complicated causes of vtof∝ p^1/4, and an explanation of the deviation from vtof ∝ p^1/6 is given from the perspective of dissipation.

关键词： discrete element method acoustic propagation packing structure stiffness tensor

Preparation of N-chloramine-Decorated AgCl Nanoparticles with Enhanced Bactericidal Activity

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Biomedical and Environmental Sciences 2020年第9期33卷 723-726页

作者： XU Jia Rong zhao Yan bao Engineering Research Center for Nanomaterials Henan UniversityKaifeng 475004HenanChina

The threat of bacteria and pathogens to human health and environmental safety has become a major public concern. In the fight against pathogenic bacteria, much effort has been expended on designing new antibacterial agents[1]. To date,various materials such as metals, oxides, Nhalamines, polymers, chitosan, and graphene have been used as antibacterial agents[2,3].

关键词： designing oxides metals

Relationship between polyhedral structures formed by tangent planes of ellipsoidal particles and system sound velocity

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Chinese Physics B 2024年第11期33卷 448-456页

作者： Cheng-Bo Li Lin bao Chuang zhao School of Materials Science and Engineering Anyang Institute of TechnologyAnyang 455000China College of Physics Guizhou UniversityGuiyang 550025China

Internal polyhedral structures of a granular system can be investigated using the Voronoi *** technique has gained increasing recognition in research of kinetic properties of granular *** systems with mono-sized spherical particles,Voronoi tessellations can be utilized,while radial Voronoi tessellations are necessary for analyzing systems with multi-sized spherical ***,research about polyhedral structures of non-spherical particle systems is *** utilize the discrete element method to simulate a system of ellipsoidal particles,defined by the equation(x a)2+(y1)2+(z 1/a)2=1,where a ranges from 1.1 to *** system is then dissected by using tangent planes at the contact points,and the geometric quantities of the resulting polyhedra in different shaped systems,such as surface area,volume,number of vertices,number of edges,and number of faces,are ***,the longitudinal and transverse wave velocities within the system are calculated with the time-of-flight *** results demonstrate a strong correlation between the sound velocity of the system and the geometry of the dissected *** sound velocity of the system increases with the increase in a,peaking at a=1.3,and then decreases as a continues to *** average volume,surface area,number of vertices,number of edges,and number of faces of the polyhedra decrease with the increase in sound *** is,these quantities initially decrease with the increase in a,reaching minima at a=1.3,and then increase with further increase of *** relationship between sound velocity and the geometric quantities of the dissected polyhedra can serve as a reference for acoustic material design.

关键词： discrete element method Voronoi tessellation polyhedral structure sound velocity

In vitro regeneration of Populus tomentosa from petioles

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Journal of Forestry Research 2017年第3期28卷 465-471页

作者： Fang Wei Fang-fang zhao bao-ming Tian School of Life Sciences Zhengzhou University

A reliable in vitro regeneration procedure for Populus tomentosa is a prerequisite for its trait improvement through genetic transformation. We established a systematic protocol for indirect regeneration of P. tomentosa using in vitro petioles of Chinese poplar cultivar ＇fasta-3＇. A high frequency of callus induction （〉97 %） was obtained from isolated petioles cultured on the modified 1/2MS basal medium supplemented with 0.5 mg/L ZT and 1.0 mg/L NAA, and the tested calli were subsequently plated on 1/2MS basal medium supplemented with 0.25 mg/L BA, 0.25 mg/L ZT, 0.25 mg/L NAA, 0.01 mg/L TDZ, and 0.5 mg/L KT for efficient regeneration of shoots after being cultured for 6 weeks. The regenerated shoots were vigorously rooted on the tested media supplemented with 1.0 mg/ L IBA and 0.5 mg/L NAA. These results can facilitate genetic transformation of P. tomentosa for trait improvements in future.

关键词： Callus induction Genetic transformation In vitro regeneration Petiole Populus tomentosa

Heavy Metal Accumulation and Ecological Responses of Turfgrass to Rubbish Compost with EDTA Addition

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Journal of Integrative Plant Biology 2005年第9期47卷 1047-1054页

作者： Li-An DUO Yu-bao GAO Shu-Lan zhao College of Chemistry and Life Sciences Tianjin Normal University Tianjin 300074 China College of Life Sciences Nankai University Tianjin 300071 China

Domestic rubbish compost is a complex-polluted system, containing multiple heavy metals, which limits its application. In the present study, Cr, Mn, Ni, Cu, Zn, Cd, and Pb accumulation and ecological responses of turfgrass to rubbish compost were investigated following the addition of EDTA. The results showed that the addition of EDTA significantly increased heavy metal accumulation in Lolium perenne L. and Festuca arundinacea L. Most heavy metal concentrations in L. perenne increased with increasing EDTA supply. The concentrations of Cr, Mn, Ni, Cu, and Cd in L. perenne were highest following the addition of 30 mmol/kg EDTA and the concentrations of Cr and Ni at this point reached concentrations of 1 914.17 and 521.25 μg/g, respectively. When the EDTA level was 〈 20 mmol/kg, the accumulation of most heavy metals in F. arundinacea increased with increasing EDTA supply, but showed a tendency to decrease at EDTA concentrations 〉20 mmol/kg. The highest concentrations of Mn, Ni, Cu, and Zn in F. arundinacea reached 268.01, 110.94, 161.52 and 1 354.97 μg/g, respectively, following the addition of 20 mmol/kg EDTA. The EDTA-induced increase in the accumulation of heavy metals in turfgrass was plantand metal-specific. L. perenne had a relatively high ability to accumulate Cr, Ni, and Zn. The highest Zn concentration was 2 979.58 μg/g and, following the addition of EDTA, the concentrations of the three metals were increased 26.23, 20.03, and 10.49-fold, respectively, compared with control. However, F. arundinacea showed a high ability to accumulate Cr, with the highest concentration （596.02 μg/g） seen following the addition of 30 mmol/kg EDTA; the concentration of Cr increased 15.51-fold compared with control. With EDTA addition, ecological responses of both turfgrass species showed that EDTA at concentrations 〈10 mmol/kg increased seed germination and aboveground net primary production （ANP） of L. perenne and slightly inhibited those of F. arundinacea, but EDTA at concentra

关键词： accumulation domestic rubbish compost EDTA heavy metal remediation turfgrass.

Bekenstein-Hawking Cosmological Entropy and Correction Term Corresponding Cosmological Horizon of Rotating and Charged Black String

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Communications in Theoretical Physics 2009年第8期52卷 264-268页

作者： zhao Ren WU Yue-Qin ZHANG Li-Chun LI huai-Fan Institute of Theoretical Physics Shanxi Datong University Datong 037009 China Department of Physics Shanxi Datong University Datong 037009 China

Utilizing the quantum statistical method and applying the new state density equation motivated by generalized uncertainty principle in quantum gravitaty, we avoid the difficulty in solving wave equation and directly calculate the partition function of bosonic and fermionic field on the background of rotating and charged black string. Then near the cosmological horizon, entropies of bosonic and fermionic field are calculated on the background of black string. When constant A introduced in generalized uncertainty principle takes a proper value, we derive Bekenstein- Hawking entropy and the correction value corresponding cosmologicaJ horizon on the background of rotating and charged black string. Because we use the new state density equation, in our calculation there are not divergent term and small mass approximation in the original brick-wall method. From the view of quantum statistic mechanics, the correction value to Bekenstein-Hawking entropy of the black string is derived. It makes people deeply understand the correction value to the entropy of the black string cosmological horizon in non-spherical coordinate spacetime.

关键词： quantum statistics nonspherical symmetry spacetime generalized uncertainty principle entropy corresponding black string cosmological horizon

A Novel Resource Allocation Method in Ultra-Dense Network Based on Noncooperation Game Theory

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China Communications 2016年第10期13卷 169-180页

作者： Zhen Wang Xiaorong Zhu Xu bao Su zhao Nanjing University of Posts and Telecommunications Nanjing China National Mobile Communications Research Laboratory Southeast University Nanjing China Department of Telecommunications Engineering Jiangsu University Zhenjiang China

In ultra-dense networks(UDNs), large-scale deployment of femto base stations is an important technique for improving the network throughput and quality of service(QoS). In this paper, a multidimensional resource allocation algorithm based on noncooperation game theory is proposed to manage the resource allocation in UDNs, including transmission point association, user channels, and power. The algorithm derives a multidimensional resource optimization model and converts into a noncooperation game model according to the analysis of transmission point association user channel and power allocation. The algorithm includes two phases: transmission point association, and channel and power allocation. Then, feasible domain and discrete variables relaxation approaches are introduced to derive an approximate optimal multidimensional resource allocation solution with low complexity. Simulation results show that this method has some advantages in suppressing interference and improves the overall system throughput, while ensuring the QoS of femtocell users.

关键词： resource allocation noncooperation game theory variables relaxation

Relationship of VEGF/VEGFR with immune and cancer cells:staggering or forward?

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Cancer Biology & Medicine 2016年第2期13卷 206-214页

作者： Yu-Ling Li Hua zhao Xiu-bao Ren Department of Biotherapy Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for Cancer Key Laboratory of Cancer Immunology and Biotherapy Research Center of Lung Cancer

Vascular endothelial growth factor(VEGF) is primarily known as a proangiogenic factor and is one of the most important growth and survival factors affecting the vascular endothelium. However, recent studies have shown that VEGF also plays a vital role in the immune environment. In addition to the traditional growth factor role of VEGF and VEGF receptors(VEGFRs), they have a complicated relationship with various immune cells. VEGF also reportedly inhibits the differentiation and function of immune cells during hematopoiesis. Dendritic cells(DCs), macrophages, and lymphocytes further express certain types of VEGF *** can be secreted as well by tumor cells through the autocrine pathway and can stimulate the function of cancer *** review will provide a paradigm shift in our understanding of the role of VEGF/VEGFR signaling in the immune and cancer environment.

关键词： Vascular endothelial growth factor (VEGF) VEGF receptors (VEGFRs) dendritic cell (DC) macrophage T lymphocyte tumor