Investigation of Liquid Cooling Plate for Server CPUs Based on Topology Optimization

In this study, a microchannel liquid cooling plate (LCP) is proposed for Intel Xeon 52.5 mm * 45 mm packaged architecture processors based on topology optimization (TO). Firstly, a mathematical model for topology optimization design of the LCP is established based on heat dissipation and pressure drop objectives. We obtain a series of two-dimensional (2D) topology optimization configurations with different weighting factors for two objectives. It is found that the biomimetic phenomenon of the topologically optimized flow channel structure is more pronounced at low Reynolds numbers. Secondly, the topology configuration is stretched into a three-dimensional (3D) model to perform CFD simulations under actual operating conditions. The results show that the thermal resistance and pressure drop of the LCP based on topology optimization achieve a reduction of approximately 20% - 50% compared to traditional serpentine and microchannel straight flow channel structures. The Nusselt number can be improved by up to 76.1% compared to microchannel straight designs. Moreover, it is observed that under high flow rates, straight microchannel LCPs exhibit significant backflow, vortex phenomena, and topology optimization structures LCPs also tend to lead to loss of effectiveness in the form of tree root-shaped branch flows. Suitable flow rate ranges for LCPs are provided. Furthermore, the temperature and pressure drop of experimental results are consistent with the numerical ones, which verifies the effectiveness of performance for topology optimization flow channel LCP.

Preliminary Model Study for Forecasting a Hot Weather Process in Guangdong Province Using CMA-TRAMS

In this paper, the CMA-TRAMS tropical high-resolution system was used to forecast a typical hot weather process in Guangdong, China with different horizontal resolutions and surface coverage. The results of resolutions of 0.02° and 0.06° were presented with the same surface coverage of the GlobeLand30 V2020, companies with the results of resolution 0.02° with the USGS global surface coverage. The results showed that, on the overall assessment the 2 km model performed better in forecasting 2 m temperature, while the 6 km model was more accurate in predicting 10 m wind speed. In the evaluation of representative stations, the 2 km model performed better in forecasting 2 m temperature and 2 m relative humidity at the coastal stations, and the 2 km model was also better in forecasting 2 m pressure at the representative stations. However, the 6 km model performed better in forecasting 10 m wind speed at the representative stations. Furthermore, the 2 km model, owing to its higher horizontal resolution, presented a more detailed stratification of various meteorological field maps, allowing for a more pronounced simulation of local meteorological element variations. And the use of the surface coverage data of the GlobeLand30 V2020 improved the forecasting of 2 m temperature, and 10 m wind speed compared to the USGS surface coverage data.

Large Eddy Simulations of Rayleigh-Bénard Convection in a Cubic Cavity

This paper conducts a Large Eddy Simulation (LES) of Rayleigh Bénard convection in a cubic cavity based on the WMLES S-Omega subgrid-scale model. For a cubic cavity with a vertical temperature difference of 6.7°C and 20°C, the velocity pulsation profiles and the mean velocity profiles of the vertical section in the middle of the cubic cavity were simulated, respectively. And they are consistent with the experiment results. Furthermore, the mean velocity field of the vertical cross-section in the middle of the cavity was calculated. Structures of the mean velocity field in the two cases are similar. A counterclockwise large vortex is found to occupy the cavity, and there are two small clockwise vortices in the lower left and upper right corners, and the mean velocity fields at two different temperature differences are consistent with the experimental results. The two-dimensional instantaneous temperature field and mean temperature field with different cross-sections in the z-direction, as well as the three-dimensional instantaneous isothermal surface structure, indicate that the large-scale circulation motion within the cubic cavity is moving diagonally. In addition, the structure of the mean streamline also illustrates this viewpoint. For the reverse vortex formed at two corners in the mean streamline structure, we used the Q criterion to identify and obtain two vortex structures similar to boomerangs. The basic turbulent structure in RB thermal convection includes the rising and falling plumes generated by buoyancy effects.

Efficient catalytic removal of COS and H_(2)S over graphitized 2D micro-meso-macroporous carbons endowed with ample nitrogen sites synthesized via mechanochemical carbonization

Developing a suitable catalyst for the elimination of highly toxic carbonyl sulfide(COS)and hydrogen sulfide(H_(2)S) is of great significance in terms of industrial safety and environmental protection.We demonstrate here the facile synthesis of graphitized 2D micro-meso-macroporous carbons by one-step carbonization of a mixture of urea and glucose at 700–900℃.The as-synthesized graphitized catalysts,designated as 2DNHPC-x(x=urea/glucose mass ratio),are endowed with an ultra-high concentration(12.9–20.2 wt%)of stable and versatile nitrogen sites(e.g.pyrrole and pyridine)which are anchored on the surface via stable covalent bonding.As a result,the 2D-NHPC-x are active in catalytic hydrolysis of COS on pyrrolic N to H_(2)S,and the H_(2)S can be subsequently captured on pyridinic N and converted to elemental sulfur at ambient conditions over the same materials.Among the prepared catalysts,2D-NHPC-x can catalytically hydrolysize 91%of COS to H_(2)S at 30℃,whereas the conversion ratio over the common catalysts g-C_(3)N_(4)and Fe_(2)O_(3)are below 6.0%.Furthermore,these catalysts also exhibit H_(2)S conversion and sulfur selectivity of nearly 100%at 180℃with long-time durability,which is higher than those of the most reported carbonbased catalysts.In contrast,the H_(2)S capacities of activated carbon,ordered mesoporous carbons(OMC)and N-doped OMC are 3.9,1.5 and2.39 mmol g^(-1),respectively.Both the experimental and theoretical results are disclosed that 2D-NHPC-x are superior to the nitrogen-doped porous materials ever applied in simultaneous catalytic elimination of both COS and H_(2)S.

Proteomic changes in rat kidney injured by adenine and the regulation of anemoside B4

Adenine is commonly used to establish the animal models for chronic kidney injury and its renal interstitial fibrosis. As an endogenous substance, adenine-induced kidney damage has not yet been fully studied and elucidated, except for inflammatory reaction. Here we analyzed the proteomics of kidney of rats after adenine overloading using LS-MS/MS assay, and observed the role of anemoside B4(B4). The results showed that adenine could down-regulate 285 proteins and up-regulate 164 proteins in rat kidney tissue compared with the normal group. Down-regulated proteins mainly affected related pathways, such as energy metabolism, while up-regulated proteins affected inflammatory response pathways and metabolic pathways. B4 could significantly reverse the down-regulation of about 40 proteins, which were involved in mitochondria, redox processes, extracellular exosomes, acetylation and other signaling pathways. Simultaneously, B4 could inhibit the up-regulation of five proteins caused by adenine, which were involved in cell cycle, oocyte meiosis, PI3 K-Akt and other signaling pathways. Further experimental results of mRNA expression using real-time PCR assay supported the proteomic analysis. Therefore, we proposed that the damage of rat kidney caused by adenine was more complicated, not only with an inflammatory reaction, but also with extensive effects to various metabolic processes in the body. This work provided a valuable clue for comprehensive understanding of adenine-induced renal damage.

CCGD-ESCC： A Comprehensive Database for Genetic Variants Associated with Esophageal Squamous Cell Carcinoma in Chinese Population

Esophageal squamous-cell carcinoma （ESCC） is one of the most lethal malignancies in the world and occurs at particularly higher frequency in China. While several genome-wide association studies （GWAS） of germline variants and whole-genome or whole-exome sequencing studies of somatic mutations in ESCC have been published, there is no comprehensive database publically available for this cancer. Here, we developed the Chinese Cancer Genomic Database-Esophageal Squamous Cell Carcinoma （CCGD-ESCC） database, which contains the associations of 69,593 single nucleotide polymorphisms （SNPs） with ESCC risk in 2022 cases and 2039 controls, survival time of 1006 ESCC patients （survival GWAS） and gene expression （expression quantitative trait loci,eQTL） in 94 ESCC patients. Moreover, this database also provides the associations between8833 somatic mutations and survival time in 675 ESCC patients. Our user-friendly database is a resource useful for biologists and oncologists not only in identifying the associations of genetic variants or somatic mutations with the development and progression of ESCC but also in studying the underlying mechanisms for tumorigenesis of the cancer. CCGD-ESCC is freely accessible at http：//db.cbi.pku.edu.cn/ccgd/ESCCdb.

Multi-omic characterization of genome-wide abnormal DNA methylation reveals diagnostic and prognostic markers for esophageal squamous-cell carcinoma

This study investigates aberrant DNA methylations as potential diagnosis and prognosis markers for esophageal squamous-cell carcinoma(ESCC),which if diagnosed at advanced stages has<30%five-year survival rate.Comparing genome-wide methylation sites of 91 ESCC and matched adjacent normal tissues,we identified 35,577 differentially methylated CpG sites(DMCs)and characterized their distribution patterns.