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褪黑素在动物中的作用研究进展

饲料工业 2017年第1期38卷 62-64页

作者：梅花丽春内蒙古民族大学动物科技学院内蒙古通辽028000

褪黑素是一种广为认知的激素,是一种高亲脂性和部分亲水性的化合物,属中性偏弱酸性,不溶于水,溶于丙酮、乙醇、乙醛等有机溶剂,受热容易破坏分布在非脊椎动物、植物、微生物、哺乳动物中,在哺乳动物中主要由松果体合成、分泌,但在视网... 详细信息

褪黑素是一种广为认知的激素,是一种高亲脂性和部分亲水性的化合物,属中性偏弱酸性,不溶于水,溶于丙酮、乙醇、乙醛等有机溶剂,受热容易破坏分布在非脊椎动物、植物、微生物、哺乳动物中,在哺乳动物中主要由松果体合成、分泌,但在视网膜、肠和副泪腺也能合成。参与动物昼夜节律的调节,具有多方面的生物学功能,包括镇痛、抗氧化、抗衰老、抗肿瘤、促进睡眠、增强免疫力等等。文章对褪黑素的合成、分泌、代谢、生物特性、动物生产中的作用、动物机体的免疫功能等几个方面进行阐述。

关键词：褪黑素免疫力抗氧化

Cage-confinement synthesis of MoC nanoclusers as efficient sulfiphilic and lithiophilic regulator for superior li–S batteries

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Rare Metals 2024年第2期43卷 624-634页

作者： Xing-Yuan Zhang mei-Na Lei Shan Tian Jian-Gan Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an710072China

High-energy-density li-S batteries are subjected to serious sulfur deactivation and short cycle lifetime caused by undesirable polysulfide shuttle effect and frantic lithium dendrite *** this work,a controllable cage-confinement strategy to fabricate molybdenum carbide(MoC)nanoclusters as a high-efficient sulfiphilic and lithiophilic regulator to mitigate the formidable issues of li-S batteries is *** sub-2 nm MoC nanoclusters not only guarantee robust chemisorption and fast electrocatalytic conversion of polysulfides to enhance the sulfur electrochemistry,but also homogenize li^(+) flux to suppress the lithium dendrite *** a consequence,the MoC-modified separator endows the batteries with boosted reaction kinetics,promoted sulfur utilization,and improved cycling stability.A reversible capacity of 701 mAh·g^(−1) at a high rate of 5.0C and a small decay rate of 0.076%per cycle at 1.0C over 600 cycles are *** study offers a rational route for design and synthesis of bifunctional nanoclusers with both sulfiphilicity and lithiophilicity for high-performance li-S batteries.

关键词： li-S batteries Nanocluster Electrocatalyst Polysulfide shuttle li dendrites

Anomalous response to creep deformation from dislocation density during electrically assisted creep aging

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Rare Metals 2024年第10期43卷 5268-5283页

作者： Chang Zhou li-Hua Zhan chun-Hui liu Ming-Hui Huang College of Mechanical and Electrical Engineering Central South University light Alloys Research Institute State Key Laboratory of Precision Manufacturing for Extreme Service PerformanceCentral South University

Adding numerous dislocations into metallic materials before the forming stage significantly enhances their deformability. However, this beneficial effect of dislocation defects may not have a simple monotonic relationship with increased dislocation density during electroplastic deformation. This is due to the complex interactions among the drifting electrons, dislocations and solute atoms. This study explores the effect of diverse initial dislocation densities on creep deformation during electrically aided creep aging of an aluminum–lithium alloy. Surprisingly, we discovered a threshold value for the dislocation density that affects electroplastic creep, i.e., an enhanced effect from dislocations weakens when exceeding this density threshold(an anomalous response to creep). Microstructural data also reveal that such an anomalous response originates mainly from differences in various dislocation density-tailored configurations, which can influence the dislocation motions and precipitation kinetics of the strengthening T1precipitates under the same action of pulsed currents. This study provides important insights into the dislocation density-mediated electroplastic creep of an aluminum–lithium alloy.

关键词： Al–Cu–li alloy Creep aging Dislocation density Pulsed currents

Highly efficient CO_(2) capture using 2-methylimidazole aqueous solution on laboratory and pilot-scale

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Chinese Journal of Chemical Engineering 2024年第3期67卷 148-156页

作者： Kun li Han Tang Shuangshuang li Zixuan Huang Bei liu chun Deng Changyu Sun Guangjin Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Zhejiang Tiandi Environmental Protection Technology Co. Ltd.Hangzhou 310012China

To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of ***,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous *** properties and sorption behaviors of this approach have been experimentally *** results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 *** selectivity for CO_(2)/N_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,***,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.

关键词： CO_(2) capture Absorption 2-Methylimidazole Separation Pilot-scale tests

Enhancing Tea Leaf Disease Identification with lightweight MobileNetV2

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Computers, Materials & Continua 2024年第7期80卷 679-694页

作者： Zhilin li Yuxin li chunyu Yan Peng Yan Xiutong li mei Yu Tingchi Wen Benliang Xie College of Big Data and Information Engineering Guizhou UniversityGuiyang550025China Power Semiconductor Device Reliability Engineering Center of the Ministry of Education Guiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China The Mushroom Research Centre Guizhou UniversityGuiyang550025China The Engineering Research Center of Southwest Bio-Pharmaceutical Resources Ministry of EducationGuizhou UniversityGuiyang550025China

Diseases in tea trees can result in significant losses in both the quality and quantity of tea *** monitoring can help to prevent the occurrence of large-scale diseases in tea ***,existingmethods face challenges such as a high number of parameters and low recognition accuracy,which hinders their application in tea plantation monitoring *** paper presents a lightweight I-MobileNetV2 model for identifying diseases in tea leaves,to address these *** proposed method first embeds a Coordinate Attention(CA)module into the originalMobileNetV2 network,enabling the model to locate disease regions ***,a Multi-branch Parallel Convolution(MPC)module is employed to extract disease features across multiple scales,improving themodel’s adaptability to different disease ***,the AutoML for Model Compression(AMC)is used to compress themodel and reduce computational *** results indicate that our proposed algorithm attains an average accuracy of 96.12%on our self-built tea leaf disease dataset,surpassing the original MobileNetV2 by 1.91%.Furthermore,the number of model parameters have been reduced by 40%,making itmore suitable for practical application in tea plantation environments.

关键词： Disease identification coordinate attention mechanism multi-scale feature extraction model pruning

Ensemble projections of climate and streamflow in a typical basin of semi-arid steppes in Mongolian Plateau of 2021-2100

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Advances in Climate Change Research 2024年第2期15卷 230-243页

作者： Hang PAN Jian-Ping TANG liang CHENG Man-chun li Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing UniversityNanjing 210023China School of Atmospheric Sciences Nanjing UniversityNanjing 210023China

The Kherlen River is the main water source for Hulun Lake,the largest lake in northern *** to reduced inflow from the Kherlen River,Hulun Lake experienced rapid shrinkage at the beginning of the 21st century,posing a serious threat to the ecological security of northern ***,there is still a significant lack of projections regarding future climate change and its hydrological response in the Kherlen River *** study analyzed the projected climate and streamflow changes in the Kherlen River basin,a vital yet vulnerable international semi-arid steppes type basin.A combination of multi-model ensemble projection techniques,and the soil and water assessment tool(SWAT)model was employed to examine the spatio-temporal changes in precipitation,temperature,streamflow,and the associated uncertainties in the *** temperature(an increase of 1.84-6.42℃)and the precipitation(an increase of 15.0-46.0 mm)of Kherlen River basin are projected to increase by 2100,leading to a rise in streamflow(1.08-4.78 m^(3) s^(-1)).The upstream of the Kherlen River exhibits remarkable increasing trends in precipitation,which has a dominant influence on streamflow of Kherlen *** increases in streamflow are observed in April,August,September,and October compared to the reference period(1971-2000).These findings suggest a partial alleviation of water scarcity in the Kherlen River,but also an increased likelihood of hydrological extreme *** projected temperature increase in the Kherlen River basin exhibits the smallest uncertainty,while more pronounced uncertainties are found in precipitation and *** spread among the results of CMIP6 models is greater than that of CMIP5 models,with lower signal-to-noise ratio(SNR)values for temperature,precipitation,and streamflow.

关键词： Climate change Flow projection Uncertainty SWAT Mongolian Plateau

Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

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Petroleum Science 2024年第3期21卷 2112-2119页

作者： Yu-Guo li Chen He chun-Mao Chen Fan liu Quan Shi State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China State Key Laboratory of Coal Mining and Clean Utilization Beijing 100013China PetroChina Ningxia Petrochemical Company Yinchuan 750021NingxiaChina

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD)and organic sulfur *** after the recovery of H_(2)S from the sour water by the stripping process,the effluent still contains a high concentration of dissolved organic sulfur(DOS),which can have a huge bad *** chemical composition of dissolved organic matter(DOM)in refinery wastewater has been extensively studied,the investigation of recalcitrant DOS from sour waters remains *** the present study,chemical composition of sour water DOMs(especially DOS)was investigated using fluorescence spectroscopy(excitation-emission matrix,EEM)and mass spectrometry,including gas chromatography-mass spectrometry(GC-MS)and high-resolution Orbitrap *** GC-MS and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process,while compounds with high hydrophilicity and humification degree were found to be more *** Orbitrap MS results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated ***,the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms,particularly in the form of highly unsaturated and aromatic *** Orbitrap MS/MS results of CHOS-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates,disulfide bonds,*** the composition and structure of sour water DOS is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur Stripping process Refinery sourwater Orbitrap MS

Charge regulation by ferromagnetic metal/liF spin-polarized interface for high-performance li metal anodes

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Rare Metals 2024年第3期43卷 995-1005页

作者： Ming-Yang Feng Shuang Zhou Yi-Fang Zhang Ya-Ping Wang chun-Yan Fu Jian-Wen li Yuan-Lang Wan Zhi-Jia Zhang Yong Jiang An-Qiang Pan State Key Laboratory of Powder Metallurgy School of Materials Science and EngineeringCentral South UniversityChangsha410083China State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Advanced Fibers and Energy StorageSchool of Material Science and EngineeringTiangong UniversityTianjin300387China School of Materials Science and Engineering Hebei University of TechnologyTianjin300130China

The interfacial characteristics of the li metal anode(LMA)play a crucial role in its overall *** various materials being applied to modify the interface,a comprehensive understanding of their specific mechanisms remains to be ***,we have prepared carbon cloth(CC)frameworks with their surfaces modified using ferromagnetic metal/liF heterogeneous films(T^(M)-liF-CC)as the substrate for LMA,which exhibit superior electrochemical *** ferromagnetic Co as a representative example,our study demonstrates that the enhanced performance of Co-liF-CC,compared to bare CC,is attributed to the spinpolarized interface contributed by the Co/liF *** and liF play individual roles in redistributing electrons and li^(+)to promote homogeneous li *** nanoparticles play a crucial role in generating strong surface capacitance by storing electrons in spin-split bands,while liF,with low surface diffusion barriers,ensures fast transportation of li^(+).The Co-liF-CC@li electrodes deliver long lives of 7400 and 3600 h at 1 and 2 mA·cm^(-2)in symmetric cells,respectively;moreover,they enable full batteries with high and durable capacities,particularly when the N/P ratios are low(3.3 or even 1.7).

关键词： lithium metal anode Interfacial charge Ferromagnetic metal lithium fluoride Spin polarization

Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan Xiu-Fang li Meng-Ya Guo mei Chen Ming Lv Rui li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index