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Influence of coarse tailings on flocculation settlement

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1065-1074页

作者： shi Wang Xue-peng song Xiao-jun Wang Qiu-song Chen Jian-chun Qin Yu-xian Ke School of Resources and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Department of Personnel Guangxi University of Science and TechnologyLiuzhou 545006China

The composition of tailings particles in mines plays a key role in the flocculation settlement of *** study the influence of coarse particle tailings(CPTs)on the flocculation settlement of tailings slurries(TSs),static flocculent settling tests,scanning electron microscopy observations,and laser particle size analyses were conducted using the tailings obtained from a copper *** results demonstrate that(i)in the accelerated and free settling process,CPTs did not directly settle at the bottom of graduated cylinders;instead,they were netted by the flocculent structures(FSs)and settled together more *** CPTs accelerate the rapid settlement of TSs;the acceleration effect is more obvious when the CPTs content is greater than 50 wt%.(ii)The most appropriate flocculant unit consumption(FUC)is 20 g·t-1,and no substantial increase is observed in the flocculant settling velocity with an increase in the flocculant because the effective FSs did not substantially change and thus did not lead to a notable increase in the settling velocity of the solid–liquid interface(SLI).(iii)In the effective settling space of the thickening facility,free water quickly flowed from the pores of FSs,which is reflected in the period from 0 to 1 min.

关键词： tailings slurry particle size distribution flocculent structures flocculating sedimentation solid–liquid interface

氧分压对猪卵母细胞成熟、受精及早期胚胎发育的影响

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广东农业科学 2013年第15期40卷 145-148页

作者：李紫聪石俊松罗绿花周荣周秀麦然标吴珍芳华南农业大学动物科学学院广东广州510642 广东温氏食品集团有限公司研究院广东新兴527439

研究利用两种氧分压(5%和20%)培养卵母细胞并进行IVF试验,同时使用两种氧分压培养孤雌(PA)胚胎、体外受精(IVF)胚胎和克隆(NT)胚胎,以探寻猪的最佳体外培养环境。结果显示:低氧分压不利于猪卵母细胞的体外成熟,其成熟率极显著低于高氧... 详细信息

研究利用两种氧分压(5%和20%)培养卵母细胞并进行IVF试验,同时使用两种氧分压培养孤雌(PA)胚胎、体外受精(IVF)胚胎和克隆(NT)胚胎,以探寻猪的最佳体外培养环境。结果显示:低氧分压不利于猪卵母细胞的体外成熟,其成熟率极显著低于高氧培养的,但对低氧培养的卵母细胞进行IVF时,其卵裂率和囊胚率均极显著高于高氧培养的卵母细胞;IVF进行精卵孵育时,低氧环境下,其胚胎卵裂率和囊胚率均显著高于高氧环境下的;PA胚胎、IVF胚胎和NT胚胎用两种氧分压培养,低氧条件下IVF胚胎的发育能力高于高氧培养的,而PA胚胎和NT胚胎差异不显著。试验结果表明,低氧培养虽不利于卵母细胞的成熟,但有利于其以后的胚胎发育,且低氧环境下IVF胚胎的发育能力高于高氧环境下的。

关键词：卵母细胞胚胎发育猪

Corrosion Behavior of the S136 Mold Steel Fabricated by Selective Laser Melting

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 68-78页

作者： shi-Feng Wen Xian-Tai Ji Yan Zhou Chang-jun Han Qing-song Wei Yu-Sheng shi State Key Laboratory of Materials Processing and Die & Mold Technology School of Materials Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Faculty of Engineering China University of Geosciences Wuhan 430074 China

The selective laser melting(SLM) method has a great potential for fabricating injection mold with complex structure. However, the microstructure and performance of the SLM molds show significantly di erent from those manufac?tured by traditional technologies. In this study, the microstructure, hardness and especially corrosion behavior of the samples fabricated by SLM and casting were investigated. The XRD results exhibit that the γ?Fe phase is only obtained in the SLM parts, and the α?Fe peak slightly moves to low di raction angle compared with casting counterparts. Due to the rapid cooling rate, the SLM samples have fine cellular microstructures while the casting ones have coarse grains with obvious elements segregation. Besides, the SLM samples show anisotropy, hardness of side view and top view are 48.73 and 50.31 HRC respectively, which are 20% higher than that of casting ones. Corrosion results show that the SLM samples have the better anti?corrosion resistance(in a 6% FeCl3 solution for 48 h) but the deeper corrosion pits than casting ones. Finally, the performance of the SLM molds could meet the requirement of injecting production. Moreover, the molds especially present a significant decrease(20%) of cooling time and increases of cooling uniform?ity due to the customized conformal cooling channels.

关键词： Selective laser melting S136 mold steel Corrosion behavior Conformal?cooling channels

Determination of inter-satellite relative position using X-ray pulsars

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第2期14卷 133-142页

作者： Da-jun FENG Lu-ping XU Hua ZHANG shi-bin song School of Electronic Engineering Xidian University Institute of Astronautics and Aeronautics Xidian University

Pulsars are rapidly rotating neutron stars that generate pulsed electromagnetic radiation.A new method for intersatellite relative position determination between a global navigation satellite system(GNSS) and spacecraft using X-ray pulsars is proposed in this *** geometric model of this method is formulated,and two different resolution algorithms are introduced and *** phase cycle ambiguity resolution is investigated,and a new strategy is proposed and *** the direct vector parameters of the pulsar,geometric dilution of precision(GDOP) is *** is shown that this method has advantages of simplicity and efficiency,and is able to eliminate the clock *** analytical results are verified numerically via computer simulations.

关键词： Pulsar navigation Position determination Phase cycle ambiguity Geometric dilution of precision(GDOP)

Programmable complex pumping field induced color-on-demand random lasing in fiber-integrated microbelts for speckle free imaging

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Science China(Information Sciences) 2023年第12期66卷 251-260页

作者： Xiaoyu shi Kaiyue SHEN Yaoxing BIAN Wanting song jun RUAN Zhaona WANG Tianrui ZHAI College of Physics and Optoelectronics Faculty of ScienceBeijing University of Technology Applied Optics Beijing Area Major Laboratory Department of PhysicsBeijing Normal University

Miniaturized lasers with on-demand color emission have immense potential in the development of integrated imaging sources. Random lasers(RLs) with cavity-free structures and low spatial coherence are promising candidates for multicolor imaging sources. However, the wide tuning range and high tuning accuracy of continuous and reversible random lasing color with a defined emissive direction remain challenging. Here, random lasing with on-demand color emission and defined emissive direction is realized in fiber-integrated microbelts through programmable pumping. Individual RL microbelts as RL units doped with blue(B)-, green(G)-, and red(R)-emissive dyes and titanium dioxide nanoparticles are assembled on an optical fiber, resulting in high-performance B/G/R lasing. The optical fiber functions as a waveguide that guides the multicolor RL to ensure a defined directional emission. By manipulating the combination of the B/G/R RL units on the waveguide, distinctive lasing colors covering the entire visible spectrum are obtained, including white-colored random lasing. To realize dynamically controllable lasing for on-demand color emission, a pumping strategy with programmable excitation is proposed by shaping the pump beams into different beam arrays for precisely pumping the RL unit combination. We envision that fiber-integrated RL sources can be implemented in various imaging applications, such as biomedical diagnosis, multiplexed communication, and optical sensing.

关键词： random laser multi-color pump control fiber-integrated directional emission

Wafer-Scale Ag₂S-Based Memristive Crossbar Arrays with Ultra-Low Switching-Energies Reaching Biological Synapses

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NANO-MICRO LETTERS 2025年第1期17卷 1-12页

作者： Zhu, Yuan Nyberg, Tomas Nyholm, Leif Primetzhofer, Daniel shi, Xun Zhang, Zhen Uppsala Univ Dept Elect Engn Div Solid State Elect S-75121 Uppsala Sweden Uppsala Univ Dept Chem Uppsala Sweden Uppsala Univ Dept Phys & Astron Uppsala Sweden Chinese Acad Sci Shanghai Inst Ceram State Key Lab High Performance Ceram & Superfine M Shanghai 200050 Peoples R China

Memristive crossbar arrays (MCAs) offer parallel data storage and processing for energy-efficient neuromorphic computing. However, most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor (CMOS) technology still suffer from substantially larger energy consumption than biological synapses, due to the slow kinetics of forming conductive paths inside the memristive units. Here we report wafer-scale Ag2S-based MCAs realized using CMOS-compatible processes at temperatures below 160 degrees C. Ag2S electrolytes supply highly mobile Ag+ ions, and provide the Ag/Ag2S interface with low silver nucleation barrier to form silver filaments at low energy costs. By further enhancing Ag+ migration in Ag2S electrolytes via microstructure modulation, the integrated memristors exhibit a record low threshold of approximately - 0.1 V, and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological synapses. The low-temperature process also enables MCA integration on polyimide substrates for applications in flexible electronics. Moreover, the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training algorithm. An impressive accuracy of 92.6% in image recognition simulations is demonstrated with the MCAs after the compensation. The demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag2S films Reactive sputter Silver nucleation Ag+ migration Energy-efficient neuromorphic computing

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： shi-Bo Feng Hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei Zhang Xiao-Mei song Yu-Ze Li Wen-Li Huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

Revealing and predicting the long-term biomechanical response of orthokeratology by developing a patient-specific computational model

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 156-168页

作者： Yifeng Li Zhuoran Yang Ziming Yan Huibin shi Zhanli Liu Kaijie Wang Department of Engineering Mechanics School of Aerospace Engineering Tsinghua University Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Lab

Orthokeratology(OK) is widely used for effective myopia correction and control. However, the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment, complicating accurate predictions of treatment outcomes. In this paper, we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal thickness. Clinical experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 months. Based on the experimental data, a patient-specific computational biomechanical model for OK was established and validated. Specifically, the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus(29.5 kPa) and tensile modulus(768.4 kPa). Additionally, a viscohyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation response. The results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation,influenced by the cornea's low shear resistance. Modeling the extended corneal relaxation time is crucial for predicting long-term biomechanical responses. The computational model effectively captures long-term changes in central corneal thickness, potentially improving OK lens fitting accuracy.

关键词： orthokeratology computational biomechanical model long-term viscoelasticity myopia correction

Quality Characteristics of Tobacco Leaves with Different Aromatic Styles from Guizhou Province,China

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Agricultural Sciences in China 2007年第2期6卷 220-226页

作者： QIN song WANG Zheng-yin shi jun-xiong College of Resources and Environmental Sciences Southwest University Chongqing 400716 P.R. China Guizhou Institute of Soil and Fertilizer Guiyang 550006 P.R.China Guizhou Tobacco Science Institute Guiyang 550003 P.R. China

The relationships between chemical components and quality indexes were studied in the tobacco leaves with different aromatic styles. A total of 16 chemical components, 4 quality indexes, and 6 smoking quality indexes from 366 tobacco leaf samples with 4 different types of aroma from Guizhou Province, China, were subjected to principal component analysis and stepwise regression analysis. The tobacco leaves with different types of aroma showed remarkable difference in the contents of chemical components, quality indexes, and smoking quality indexes. The first principal factors （carbohydrates and nitrogen-containing compounds） of the chemical composition of the leaf were similar among different types of aroma, which showed that the quality of the leaf was mainly influenced by carbohydrates and nitrogen-containing compounds and their ratios. The factors for the second through the seventh principal components varied largely among varioUs aromatic types, suggesting the contribution of other chemical components to the leaf quality. In addition, the smoking quality of four different aromatic leaves showed significant correlation with the different chemical components. The quality of tobacco leaves with different types of aroma was influenced by multiple factors, especially ecological conditions and culture techniques, which may provide guidance for directive cultivation of high-quality tobacco leaves.

关键词： tobacco (Nicotiana tabacum L.) Guizhou Province type of aroma quality