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Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang Qing Shi Guofan Zhang Yuxuan zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Correlation Analysis on Single Nucleotide Polymorphism of CAPN1 Gene and Meat Quality and Carcass Traits in Chickens

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Agricultural Sciences in China 2007年第6期6卷 749-754页

作者： ZHANG Zeng-rong zhu Qing LIU yi-ping College of Animal Science and Technology Sichuan Agricultural University Yaan 625014 P.R.China

The selection of meat quality has received considerable focus in chicken breeding. This study was aimed at investigating the effect of CAPN1 gene on meat quality traits in chicken populations. Primer pairs for 3 UTR in CAPN1 were designed from database of chicken genomic sequence. Polymorphisms were detected using PCR-SSCP and DNA sequencing. A mutation at position 9 950 nt （G/A, locus A） was found among individuals in each population. The allele and genotype frequencies significantly differed among eight lines with higher frequencies of allele A2 and genotype AIA2 （P〈0.01）. The least square analysis showed that there was significant difference （P 〈 0.05） in muscle fiber density and some carcass traits among genotypes and that the breast muscle fiber density （BFD） of birds ofAIA1 genotype was significantly higher （P〈0.05） than that of birds ofA2A2 genotype. It was concluded that the CAPN1 gene was the major gene affecting the muscle fiber traits of chicken or was linked with the major gene. These results were useful for studying the molecular mechanism that influences meat traits and were used as the base of molecular-assisted selection to meat quality traits. So, this site may be a potential marker affecting the muscle traits of chickens.

关键词： chicken muscle fiber carcass traits CAPNI SNPs

DESIGN AND FABRICATION OF HIGH-PERFORMANCE INFRARED HOLLOW FIBER FOR MEDICAL LASER POWER DELIVERY

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Journal of Innovative Optical Health Sciences 2009年第1期2卷 101-106页

作者： yi-WEI SHI XIAO-SONG zhu KE-rong SUI XIAO-LI TANG Department of Communication Science and Engineering Fudan University Shanghai 200433 China

We proposed a method to evaluate the material dispersion of the dielectric film in dielectriccoated silver hollow *** taking into consideration the derived material dispersion,the wavelengths of the loss peaks and valleys in the loss spectra of the hollow fiber can be predicted more ***,we fabricated the dielectric-coated silver hollow fiber according to the parameters obtained by using the improved design *** measured data showed good agreement with the calculated *** loss for medical laser of Er:YAG and CO_(2)was less than 0.3 dB/*** loss for green or red pilot beams was around 5 dB/m,which is sufficiently low for the purpose of pilot beam *** derived material dispersion plays an important role in the design and fabrication of the hollow fiber for multiwavelength delivery.

关键词： Waveguide medical laser calculus fragmentation dielectric film

The Existence of Weak Solutions to the 2D Euler Equations with Initial Vorticity in BMO

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1881-1888页

作者： Xiang rong zhu Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

We shall prove that there exists a weak solution to the 2D Euler equations with initial vorticity in BMO and initial velocity in L^∞.

关键词： Euler equation weak solution BMO

Jacobian-determinant Equation in the Critical Besov Spaces

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Acta Mathematica Sinica,English Series 2017年第5期33卷 691-704页

作者： Xiang rong zhu Department of Mathematics Zhejiang Normal University Jinhua 321004 P. R. China

Let Ω be a bounded domain in R;with smooth boundary. Here we consider the following Jacobian-determinant equation det u（x）=f（x）,x∈Ω;u（x）=x,x∈?Ω where f is a function on Ω with min;f = δ > 0 and Ωf（x）dx = |Ω|. We prove that if f ∈B;（Ω） for some p∈（n,∞）, then there exists a solution u ∈ B;（Ω）C;（Ω） to this equation. On the other hand, we give a simple example such that u ∈ C;（R;, R;） while detu does not lie in B;（R;） for any p<∞.

关键词： Jacobian-determinant Besov space elliptic system Neumann problem

Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China Life Sciences 2025年第1期 144-157页

作者： Huanbo zhu Longtao Huangfu Junbing Chen Jiafu Ji Xiaofang Xing Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute Department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute Department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

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Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe Sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

Defect Engineering with Rational Dopants Modulation for High-Temperature Energy Harvesting in Lead-Free Piezoceramics

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Xi, Kaibiao Guo, Jianzhe Zheng, Mupeng zhu, Mankang Hou, Yudong Beijing Univ Technol Coll Mat Sci & Engn Key Lab Adv Funct Mat Minist Educ Beijing 100124 Peoples R China

High temperature piezoelectric energy harvester (HT-PEH) is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors. However, simultaneously excellent performances, including high figure of merit (FOM), insulation resistivity (rho) and depolarization temperature (T-d) are indispensable but hard to achieve in lead-free piezoceramics, especially operating at 250 degrees C has not been reported before. Herein, well-balanced performances are achieved in BiFeO3-BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping. Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization, regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole, comprehensive excellent electrical performances (T-d = 340 degrees C, rho(250) (degrees C) > 10(7) Omega cm and FOM2(50 degrees C) = 4905 x 10(-15 )m(2) N-1) are realized at the solid solubility limit of manganese ions. The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250 degrees C with high energy conversion efficiency (eta = 11.43%). These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements, paving a new way in developing self-powered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

Proportional directional valve based automatic steering system for tractors

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Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 458-464页

作者： Jin-yi LIU Jing-quan TAN En-rong MAO Zheng-he SONG Zhong-xiang zhu Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment China Agricultural University

Most automatic steering systems for large tractors are designed with hydraulic systems that run on either constant flow or constant pressure. Such designs are limited in adaptability and applicability. Moreover, their control valves can unload in the neutral position and eventually lead to serious hydraulic leakage over long operation periods. In response to the problems noted above, a multifunctional automatic hydraulic steering circuit is presented. The system design is composed of a 5-way-3-position proportional directional valve, two pilot-controlled check valves, a pressure-compensated directional valve, a pressurecompensated flow regulator valve, a load shuttle valve, and a check valve, among other components. It is adaptable to most open-center systems with constant flow supply and closed-center systems with load feedback. The design maintains the lowest pressure under load feedback and stays at the neutral position during unloading, thus meeting the requirements for steering. The steering controller is based on proportional-integral-derivative(PID) running on a 51-microcontroller-unit master control chip. An experimental platform is developed to establish the basic characteristics of the system subject to stepwise inputs and sinusoidal tracking. Test results show that the system design demonstrates excellent control accuracy, fast response, and negligible leak during long operation periods.

关键词： Automatic steering system Hydraulic circuit Proportional directional valve Proportional-integral-derivative(PID) control