Numerical simulation of aluminum holding furnace with fluid-solid coupled heat transfer

To predict three-dimensional temperature distribution of molten aluminum and its influencing factors inside an industrial aluminum holding furnace,a fluid-solid coupled method was presented.The fluid-solid coupled mathematics models of aluminum holding furnace in the premixed combustion processing were established based on mass conservation,moment conservation,momentum conservation,energy conservation and chemistry species conservation.Computational results agree well with the test data of the typical condition.The maximum combustion temperature is 1 850 K.The average temperature of the molten aluminum is 1 158 K,and the maximum temperature difference is about 240 K.The average temperature increases 0.3 ℃ while the temperature of combustion air increases 1 ℃.The optimal excess air ratio is 1.25-1.30.

Dynamic Simulation of Volume Fraction and Density Solid Phase Effect on Phase Hold-Up in 3 Phase Fluidize Bed Column through CFD

The gas-liquid-solid fluidized bed has emerged in recent years as one of the most promising devices for three-phase operation. Selection and design is one of them in parameter in the performance of three phase system. This paper focuses on volume fraction and density effect on the phases hold-up in a 3 phase fluidize bed column containing liquid phase with 100 cm height and 20 cm diameter, in this case the solid phase with 0.15, 0.25, 0.35 volume fraction and density 2470, 3000, 4000, 5000 m3 dispersion into liquid phase and the gas phase enter the column through a sparger of 2 cm diameter with 0.02 m/s velocities. The results show as the solid phase volume fraction increases from 0.02 to 0.08 m/s. The gas hold-up decreases and solid hold-up increases. Solid phase density increases, so solid phase hold-up decreases and gas hold-up decreases.

Design of Track/Hold (T/H) Circuit of Broad Bandwidth and High Speed Pipeline Structure ADC Based on the Super Frequency Application

A track/hold （T/H） circuit of broad bandwidth high speed pipeline structure ADC based on the super frequency application is designed in the paper. Some main factors affecting SNR of high speed ADC, such as aperture uncertainty, switch capacitor, and MOS switch, are analyzed. In the circuit, the full-differential structure and the bottom plate sampling technique are adopted to optimize the switch capacitors and MOS switches. The result based on the Spectre simulation on 0.35pm Bi- CMOS technology indicate that the aperture uncertainty, charge-injection, and non-linearity of clock feed-through are considerably restrained and the performance of T/H circuit is enhanced

Jiangsu Dyed-yarn Weaving Group Holdings Co. Ltd

The high-quality seersucker series products, produced by the Jiangsu Dyed-Yarn Weaving Group Holdings Co. Ltd. are selling well on the international textiles market. The predecessor of the company was the Tongzhou City Shuangmeng Cloth Weaving Mill, a small factory run by the township. Its Flying Wing brand yarn-dyed seersucker enjoys a

Inner Mongolia Baotou Double Ring Chemicals (Group) Holdings Co. Ltd

The Inner Mongolia Baotou Double Ring Chemicals (Group) Holdings Co. Ltd is a key enterprise producing calcium carbide assigned by the Ministry of Chemical Industry. Its products include calcium carbide, dissolved acetylene and electrode paste. Since 1980 it has exported calcium carbide products to Japan, Australia, the Republic of Korea, Pakistan, India, southeast Asia and other countries and regions, with annual exports of 15,000-20,000 tons. It has become the largest enterprise in China exporting calcium carbide. The Double Ring brand calcium carbide won a gold prize from

Nation always Upholds People-centered Rights

China has always upheld the people-centered perspective on human rights and takes the path to effectively meet the people’s ever-growing need for a better life,experts said at an online meeting on Monday.The online meeting was a side event of the 51st session of the United Nations Human Rights Council.

China holds the secretariat of ISO/TC 341 on heat supply network

The inauguration of the secretariat of ISO/TC 341,Heat supply net work,was held in Beijing on April 11.China Urban Construction Design&Research Institute,a subordinate enterprise of China Construction Technology Consulting Co.,Ltd.(CCTC),holds the secret ariat,which is China’s first ISO secretariat for standardization in the field of housing and urban-rural development.

Setting up State Holding Corporations——an Interview with He Boquan, Vice President of the China National Nonferrous Industry Corporation

An announcement was made on November 4, 1994, on making the China National Nonferrous Industry Corporation one of the three State holding corporations for experiment at a national conference on experimenting on modern enterprises sponsored by the State Council. The appearance of State holding corporations is the result of China’s deepening economic restructuring and an important and integral part of deepening enterprise reform.

A Phoenix Reborn An Interview with Zhong Shan, Chairman of the Board and General Manager of the Zhejiang Zhongda Group Holding Co Ltd

After series of reforms including the introduction of the shareholding system, re-organization of capital, expansion of business fields and scale through cooperation or merge with other enterprises,Zhongda Group has now become a comprehensive enterprise group integrating import and export, foreign and domestic trade, ?and industry and serviceS.In the past five years stan-

Effect of sintering temperature and holding time on structure and properties of Li_(1.5)Ga_(0.5)Ti_(1.5)(PO_4)_(3)electrolyte with fast ionic conductivity

Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explore the effects of sintering temperature and holding time on relative density,phase composition,microstructure,bulk conductivity,and total conductivity.In the impedance test under frequency of 1-10^(6) Hz,the bulk conductivity of the samples increased with increasing sintering temperature,and the total conductivity first increased and then decreased.SEM results showed that the average grain size in the ceramics was controlled by the sintering temperature,which increased from(0.54±0.01)μm to(1.21±0.01)μm when the temperature changed from 750 to 950°C.The relative density of the ceramics increased and then decreased with increasing temperature as the porosity increased.The holding time had little effect on the grain size growth or sample density,but an extended holding time resulted in crack generation that served to reduce the conductivity of the solid electrolyte.

Advancing sustainability:Magnesium-based solutions for environmental challenges and high-performance technologies in superconductivity

The Journal of Magnesium and Alloys(JMA)is actively dedicated to addressing crucial issues related to energy con-servation,emission reduction,energy crises,and sustainable development[1].Magnesium,recognized as the lightest com-mercial structural metal and a promising energy storage ma-terial,holds immense potential in contributing to strategic objectives such as achieving“carbon neutrality”and the“emission peak”,thus mitigating the ongoing energy cri-sis[2].JMA diligently reports on various research fronts,including magnesium-based structural materials,magnesium batteries,magnesium-based hydrogen storage materials,and magnesium-based superconducting super magnets[3].

Impacts of bus holding strategy on the performance and pollutant emissions of a two-lane mixed traffic system

This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissions of passenger cars.The dynamic behaviors of these two types of vehicles are described using cellular automata(CA)models under open boundary conditions.Numerical simulations are carried out to obtain the phase diagrams of the bus system and the trajectories of buses and passenger cars before and after the implementation of the bus holding strategy under different probabilities of passenger cars entering a two-lane mixed traffic system.Then,we analyze the flow rate,satisfaction rate,and pollutant emission rates of passenger cars together with the performance of a mixed traffic system.The results show that the bus holding strategy can effectively alleviate bus bunching,whereas it has no significant impact on the flow rate and pollutant emission rates of passenger cars;the flow rate,satisfaction rate,and pollutant emission rates of passenger cars for either the traffic system or for each lane are influenced by the bus departure interval and the number of passengers arriving at bus stops.

Upholding Responsibility Power Construction Corporation of China fulfills social responsibility in southeast Africa

“Welcome to the heart of power,I the heart of energy,the source of energy.Thank you,the days and nights I worked here have kept my heart in my thoughts…”Shangwaya Reuben,an employee of Power Construction Corporation of China(POWERCHINA)Zambian Branch,sang.Reuben has been working for the company for nearly 10 yeai s.Although he is not very eloquent,he has put his respect for Chinese people and love for POWERCHINA into the song,which not only expresses the feeling of gratitude of millions of Zambian people,but also vividly highlights the valuable friendship between the two peoples.

Characterization of Hydroxyapatite Extracted from Crab Shell Using the Hydrothermal Method with Varying Holding Times

Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.

‘Oversupply’Doesn't Hold Much Water

"The golden time for China’s textile industry development is coming up," said Mr. Du Yuzhou, President of China National Textile and Apparel Council. Du accentuated this remark in response to a recent statement simply alleging that 86.9% of 84 textile and apparel categories got oversupplied.

Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment

The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery.

Application of a 2 Parameter Weibull Distribution in Modeling of State Holding Time in HIV/AIDS Transition Dynamics

This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Failure Time (AFT) model, Cox Proportional Hazards model, and Survival model, we assess the effectiveness of these models in capturing survival rates across varying gender, age groups, and treatment categories. Simulated data was used to fit the models, with model identification criteria (AIC, BIC, and R2) applied for evaluation. Results indicate that the AFT model is particularly sensitive to interaction terms, showing significant effects for older age groups (50 - 60 years) and treatment interaction, while the Cox model provides a more stable fit across all age groups. The Survival model displayed variability, with its performance diminishing when interaction terms were introduced, particularly in older age groups. Overall, while the AFT model captures the complexities of interactions in the data, the Cox model’s stability suggests it may be better suited for general analyses without strong interaction effects. The findings highlight the importance of model selection in survival analysis, especially in complex disease progression scenarios like HIV/AIDS.

信息通信技术行业标准必要专利许可费计算方法研究——基于TCL对爱立信和UP对华为案的比较

为了避免专利劫持和许可费堆叠,标准制定组织通常要求标准必要专利权利人在加入标准组织时承诺以FRAND原则进行专利许可。然而,由于FRAND原则本身的模糊性,导致该原则下标准必要专利许可费计算成为争论的焦点。TCL对爱立信和Unwired Planet对华为案是信息通信技术行业近两年来涉及FRAND许可费非常有影响力的案件,两案均采用"自上而下法"和"可比较许可协议法"对许可费进行了详细计算。然而由于两案对两种方法的具体适用不同,导致判决结果存在很大差异,两案中华为公司和TCL公司均是标准必要专利受让方。本文通过比较分析两个案件对上述两种许可费计算方法的具体适用,找出其差异,以期对中国许可费计算的理论和司法实践,以及信息通信技术企业应对国际标准必要专利许可、促进标准必要专利创新提供启示。

基于排队论模型的蓝牙Hold模式再利用研究

文章调查了蓝牙技术在低速率的网络应用中存在的问题,以排队论模型为基础,对蓝牙低能耗保持模式(Hold)进行了深入的分析和再利用研究。研究表明,蓝牙运行在低速率时,重复性使用Hold模式可减少系统的通信时间,提高系统利用率。仿真和结果验证表明,当Hold时间参数不变和采用较大的基带数据分组类型,例如3-DH5,将减少蓝牙通信时间,提高系统利用率。此外,根据应用速率特点,结合Hold模式再利用的传输方式,合理地设置Hold时间、通信时间和硬件缓存大小等参数,可优化整个系统的成本和运行时的功率消耗。