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Sn引入方式对Al_(2)O_(3)负载Pt基催化剂丙烷脱氢性能的影响

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石油化工高等学校学报 2024年第4期37卷 49-56页

作者：韩飞飞焦建豪田祥臣杨野秦玉才宋丽娟辽宁石油化工大学石油化工学院辽宁抚顺113001 中国石油大学(华东)化学工程学院山东青岛266000

Sn助剂可有效提高丙烷脱氢Pt基催化剂的丙烯选择性并抑制积碳的产生,但是Sn的助剂效应尚不明晰。采用共浸渍法和溶胶凝胶法调变Sn的引入方式,构建不同PtSn作用体系,并系统地探究了Sn引入方式对Pt基催化剂丙烷脱氢反应性能的影响;采用XRD... 详细信息

Sn助剂可有效提高丙烷脱氢Pt基催化剂的丙烯选择性并抑制积碳的产生,但是Sn的助剂效应尚不明晰。采用共浸渍法和溶胶凝胶法调变Sn的引入方式,构建不同PtSn作用体系,并系统地探究了Sn引入方式对Pt基催化剂丙烷脱氢反应性能的影响;采用XRD、BET对催化剂的织构性质进行表征,通过H_(2)-TPR、TEM、CO-IR对助剂Sn的结构进行辨析,并对催化剂进行了丙烷脱氢反应性能评价与积碳分析。结果表明,相较于共浸渍法制备的PtSn/γ-Al_(2)O_(3),溶胶凝胶法制备的Pt/Sn-γ-Al_(2)O_(3)具有较低的比表面积和较大的孔径,可促进PtSn团簇与载体间的相互作用,实现金属的高分散度;Pt/Sn-γ-Al_(2)O_(3)有较多的活性位,因此丙烷转化率和丙烯收率较高,同时载体的大孔径也使催化剂的积碳量显著降低。

关键词：助剂Sn 引入方式丙烯 PtSn催化剂

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Analysis of Sulfate Corrosion Resistance and Reliability of Recycled Concrete

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Wuhan University Journal of Natural Sciences 2020年第3期25卷 208-216页

作者： QIAO Hongxia ZHU xiangchen CHEN Kefan PENG Kuan College of Civil Engineering Lanzhou University of TechnologyLanzhou 730000GansuChina

In order to study the effect of different recycled fine aggregate and recycled coarse aggregate substitution rate on the sulfate resistance of recycled concrete under dry-wet cycle conditions,the substitution rate of recycled fine aggregate and recycled coarse aggregate was designed to be 0%/0%,10%/0%,0%/25%,10%/25%,0%/50%and 10%/50%of the six groups of mixture *** mass loss rate and relative dynamic modulus of each group of test blocks were tested respectively and the optimal ratio was *** Wiener distribution probability method was used to establish the reliability function to optimize the remaining life of the *** results show that the dynamic elastic modulus and mass show a trend of increasing first and then decreasing during the dry-wet cycles of *** recycled concrete has the strongest resistance to sulfate attack under the substitution rate of recycled fine aggregate and recycled coarse aggregate is 10%and 0%,and the test blocks will be damaged after being subjected to 182 times of dry-wet cycles of *** effect of recycled coarse aggregate on the sulfate attack resistance of the test block is more obvious than that of the recycled fine aggregate,which leads to the durability of the concrete being greatly reduced.

关键词： recycled concrete dry-wet cycles of sulfate the Wiener distribution probability microscopic reaction mechanism

广西不同地区养殖黄沙鳖肌肉的营养成分分析与品质评价

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饲料工业 2024年第10期45卷 91-97页

作者：农珍珍韦玲静叶香尘刘康卢玉典严雪瑜张盛广西北部湾海洋生物多样性养护重点实验室北部湾大学海洋学院广西钦州535011 广西壮族自治区水产引育种中心广西南宁530031

为探究不同养殖地区黄沙鳖营养成分含量差异,对其肌肉营养组成进行分析,为其营养价值评估提供理论基础。试验选取广西桂平、南宁、玉林3个地区不同养殖场健康的黄沙鳖各30只,对其矿物质元素、常规营养成分、氨基酸和脂肪酸含量等营养成... 详细信息

为探究不同养殖地区黄沙鳖营养成分含量差异,对其肌肉营养组成进行分析,为其营养价值评估提供理论基础。试验选取广西桂平、南宁、玉林3个地区不同养殖场健康的黄沙鳖各30只,对其矿物质元素、常规营养成分、氨基酸和脂肪酸含量等营养成分进行测定和分析。结果显示:常规营养方面,南宁黄沙鳖肌肉中水分和粗蛋白含量最高;玉林黄沙鳖肌肉中灰分含量偏低,但其粗脂肪含量显著高于桂平黄沙鳖(P<0.05)。矿物质方面,常量元素中镁和钙含量最丰富,其中南宁黄沙鳖肌肉中镁含量最高,桂平黄沙鳖肌肉中钙含量偏高;微量元素中,3个地区黄沙鳖肌肉的铁和锌含量相对较高,且玉林黄沙鳖肉的微量元素含量(锰、锌除外)均高于桂平和南宁黄沙鳖。氨基酸方面,3个地区鳖肉检测出的16种氨基酸中,谷氨酸(Glu)含量最多,其次为天冬氨酸(Asp),必需氨基酸/总氨基酸(ΣEAA/ΣTAA)和必需氨基酸/非必需氨基酸(ΣEAA/ΣNEAA)的比值分别为37.05%~38.34%和70.04%~74.23%,联合国粮农组织/世界卫生组织(FAO/WHO)氨基酸评分标准模式中推荐的40%和60%的理想蛋白质比值相近;游离氨基酸/总氨基酸(ΣFAA/ΣTAA)为39.45%~40.76%,且必需氨基酸指数(EAAI)介于65.14~81.42之间。桂平黄沙鳖肌肉的氨基酸总量(ΣTAA)、非必需氨基酸总量(ΣEAA)、游离氨基酸总量(ΣFAA)及EAAI均为最高。脂肪酸组成方面,其种类均超过20种,桂平和南宁黄沙鳖肌肉中二十碳五烯酸+二十二碳六烯酸(EPA+DHA)含量较高。综上所述,养殖地区的差异,黄沙鳖间肌肉营养成分各具特色。

关键词：黄沙鳖营养成分肌肉品质氨基酸脂肪酸

Application of Auger electron spectroscopy in lithium-ion conducting oxide solid electrolytes

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Nano Research 2023年第3期16卷 4039-4048页

作者： Yue Zhang Wenbo Zhai xiangchen Hu Yilan Jiang Shaojie Chen Yining Zhang Wei Liu Yi Yu School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Key Laboratory of High-resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210China

Garnet-type oxide solid electrolytes are the critical materials for all-solid-state lithium ion *** spectroscopic analysis on solid electrolytes plays a key role in bridging the gap between microstructure and *** this work,Auger electron spectroscopy(AES),which can directly detect lithium element and distinguish its valence state,was applied to characterize the garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6O12)(LLZTO).Different spectroscopy parameters were evaluated and optimal acquisition conditions were *** induced precipitation of lithium metal from LLZTO was *** exploring the influence factors of precipitation and combining transmission electron microscopy(TEM)and focused ion beam(FIB)experiments,the underlying mechanism of the phenomenon was revealed and previous controversy was *** analysis method was also extended to other types of solid electrolytes,and this work provides a reference for future in-depth research on the structure-property relationship of solid electrolytes using AES.

关键词： Auger electron spectroscopy solid electrolyte garnet-type Li6.4La3Zr1.4Ta0.6O12 lithium metal precipitation

Signal acquisition of Luojia-1A low earth orbit navigation augmentation system with software defined receiver

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Geo-Spatial Information Science 2022年第1期25卷 47-62页

作者： Liang Chen xiangchen Lu Nan Shen Lei Wang Yuan Zhuang Ye Su Deren Li Ruizhi Chen State Key Laboratory Of Information Engineering In Surveying Mapping And Remote SensingWuhan UniversityWuhanChina

Low Earth Orbit(LEO)satellite navigation signal can be used as an opportunity signal in the case of a Global Navigation Satellite System(GNSS)outage,or as an enhancement by means of traditional GNSS positioning *** matter which service mode is used,signal acquisition is a prerequisite for providing enhanced LEO navigation *** with the medium orbit satellite,the transit time of the LEO satellite is ***,it is of great significance to expand the successful acquisition time range of the LEO *** studies on LEO signal acquisition are based on simulation ***,signal acquisition research based on real data is *** this work,the signal characteristics of LEO satellites:power space density in free space and the Doppler shift of LEO satellites are individually *** unified symbolic definitions of several integration algorithms based on the parallel search signal acquisition algorithm are *** verify these algorithms for LEO signal acquisition,a Software Defined Receiver(SDR)is *** performance of these integration algorithms on expanding the successful acquisition time range is verified by the real data collected from the Luojia-1A *** experimental results show that the integration strategy can expand the successful acquisition time range,and it will not expand indefinitely with the integration *** performance of the coherent integration and differential integration algorithms is better than the other two integration algorithms,so the two algorithms are recommended for LEO signal acquisition and a 20 ms integration duration is *** detection threshold of 2.5 is not suitable for all integration algorithms and various integration durations,especially for the Maximum-to-Mean Ratio indicator.

关键词： Coherent integration differential coherent integration Low Earth Orbit(LEO) non-coherent integration navigation augmentation signal acquisition

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饲喂全株青贮玉米对藏香猪肠道微生物的影响

中国畜牧兽医 2024年第2期51卷 530-539页

作者：吴丹宁张亚南黄涛周晓龙汪涵李向臣李洪军文军张琪赵阿勇杨松柏浙江农林大学动物科技学院/动物医学院浙江省畜禽绿色生态健康养殖应用技术研究重点实验室临安311300 阿坝州博文农牧科技有限公司九寨沟623402 九寨沟县科学技术和农业畜牧局九寨沟624603

[目的]探究饲粮中添加全株青贮玉米对藏香猪肠道微生物菌群的影响。[方法]选用日龄和体重((24.26±2.78)kg)相近的藏香猪40头,公母各半,随机分为两组,对照组和试验组,每组20头。对照组饲喂基础饲粮,试验组以30%全株青贮玉米等量替代基... 详细信息

[目的]探究饲粮中添加全株青贮玉米对藏香猪肠道微生物菌群的影响。[方法]选用日龄和体重((24.26±2.78)kg)相近的藏香猪40头,公母各半,随机分为两组,对照组和试验组,每组20头。对照组饲喂基础饲粮,试验组以30%全株青贮玉米等量替代基础饲粮,饲喂时间为7个月。饲养试验结束后采集粪样共40份,每组20份。利用16S rRNA基因测序技术分析全株青贮玉米对藏香猪肠道微生物组成和结构的影响。[结果]两组共鉴定出19个门、33个纲、67个目、123个科、277个属、524个种。其中厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidota)是藏香猪肠道微生物优势门。试验组肠道微生物Shannon指数显著低于对照组(P<0.05)。利用Wilcoxon秩和检验的方法进行两组比较分析发现,与对照组相比,试验组藏香猪肠道微生物中螺旋体门(Spirochaetota)、纤维杆菌门(Fibrobacterota)、密螺旋体属(Treponema)、乳杆菌属(Lactobacillus)和链球菌属(Streptococcus)相对丰度显著升高(P<0.05);放线菌门(Actinobacteriota)、变形菌门(Proteobacteria)和Christensenellaceae_R-7_group相对丰度显著减少(P<0.05)。LEfSe分析结果显示,试验组非解乳糖链球菌(Streptococcus alactolyticus)和嗜淀粉乳杆菌(Lactobacillus amylovorus)丰度显著高于对照组(P<0.05)。[结论]饲喂全株青贮玉米改变了藏香猪肠道微生物菌群的结构,提高了有益菌的相对丰度,可对肠道健康产生积极的影响。

关键词：全株青贮玉米藏香猪肠道微生物

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底吹搅拌技术在电弧炉中的应用与发展

特殊钢 2024年第2期45卷 1-7页

作者：贺庆姚同路李相臣赵进宣赵舸钢铁研究总院有限公司冶金工艺研究所北京100081

发展电弧炉短流程炼钢是钢铁工业实现“双碳”目标的重要途径。近年来,现代电弧炉技术发展迅速,电弧炉底吹搅拌技术也在不断进步和推广,对电弧炉生产的高效化和节能化作出了重要贡献。针对电弧炉底吹搅拌技术的机理、工艺特点、系统组... 详细信息

发展电弧炉短流程炼钢是钢铁工业实现“双碳”目标的重要途径。近年来,现代电弧炉技术发展迅速,电弧炉底吹搅拌技术也在不断进步和推广,对电弧炉生产的高效化和节能化作出了重要贡献。针对电弧炉底吹搅拌技术的机理、工艺特点、系统组成、气体种类、底吹元件类型及工艺布置方式进行综述,并对底吹技术的应用情况进行总结分析。模拟计算得出,远离底吹装置的区域,钢液流速明显偏低。结合炉型特点布置底吹装置及优化底吹气量,可改善熔池动力学条件,促进钢液元素传质,实现降低能耗和原材料消耗、提高生产效率的效果。深度开展底吹技术研发,与吹炼、供电、喷粉等工艺技术耦合,并结合新炉型特点制定底吹工艺制度,实现智能化底吹是发展现代电弧炉短流程技术的重要方向。

关键词：电弧炉短流程炼钢底吹搅拌数值模拟搅拌能

A Multifunctional {P_(2)Mo_(5)}-based Hybrid Applying to Catalysis, Electrocatalysis and Dye Adsorption

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Chemical Research in Chinese Universities 2022年第6期38卷 1553-1560页

作者： LIU Xiaodong WANG xiangchen XU Na ZHANG Zhong LI Xiaohui LIU Guocheng WANG Xiuli Liaoning Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell College of Chemistry and Materials EngineeringBohai UniversityJinzhou121013P.R.China

As a common environmental pollutant, thioether can cause serious environmental pollution, so selective oxidation of thioether has become one of the current research hotspots. In this paper, an inorganic-organic hybrid based on a Standberg-type polyoxometalate, [Hbiz]_(5)[HP_(2)Mo_(5)O_(23)]·5H_(2)O(1)(biz=benzimidazole), was obtained by adjusting pH under hydrothermal conditions. The structure was characterized by infrared spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Compound 1 can be used as an excellent catalyst for the oxidation of thioanisole. The experimental results showed that thioanisole could be catalytically oxidized to methyl phenyl sulfoxide by compound 1 as a catalyst within 40 min. The conversion rate and selectivity reached 99%. Compound 1 had good cycling stability as a heterogeneous catalyst. In addition, the electrocatalytic reduction of H_(2)O_(2) and Cr_(2)O_(7)^(2−) for hybrid 1 was preliminarily investigated. In addition, the adsorption performance of hybrid 1 on cationic dye crystal violet and methylene blue was tested, and the adsorption efficiencies can reach 98.5% and 86.3%, respectively.

关键词： Polyoxometalate Catalysis Electrocatalysis Dye adsorption

高水平摔跤运动员关键技术指标与运动成绩关联性分析

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中国体育教练员 2024年第2期32卷 17-19,23页

作者：白银川许奎元周胜银李祥晨国家体育总局体育科学研究所北京100061 北京体育大学北京100084

运用皮尔逊(Pearson)相关性分析和逐步回归分析法,对高水平摔跤运动员的关键技术指标与运动成绩之间的关系进行研究。结果表明:运动成绩与VT(双肩获胜)的使用次数的相关性不大,与ST(比分优势获胜)的使用次数和防守效率呈显著正相关,与... 详细信息

运用皮尔逊(Pearson)相关性分析和逐步回归分析法,对高水平摔跤运动员的关键技术指标与运动成绩之间的关系进行研究。结果表明:运动成绩与VT(双肩获胜)的使用次数的相关性不大,与ST(比分优势获胜)的使用次数和防守效率呈显著正相关,与进攻效率和技术全面性呈显著负相关;防守效率对运动成绩有显著的正向影响,技术全面性对运动成绩产生显著的负向影响。逐步回归与皮尔逊(Pearson)相关分析的结果相一致,进一步证实在现行规则下当运动员进攻能力相当时,突出的防守能力、技术动作的全面性和成功率对运动成绩起决定性作用。

关键词：摔跤高水平运动员技战术关键指标运动成绩