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China Petroleum Processing & Petrochemical Technology 2009年第2期11卷 27-30页

作者： Tao Haiqiao Long Jun Zhou Han Xie Chaogang Dai Zhenyu wei xiaoli SINOPEC Research Institute of Petroleum Processing Beijing 100083 SINOPEC Changling Branch Company

The structure and energy of the carbonium ions formed upon protonation of butane were studied by the DFT methods. Four stable structures are identified for the protonated form of n-butane, the energy increases in the following order： C2HC3〈C1HC2〈C2HH〈C1HH, and the stability decreases in the following order C2HC3〉C1HC2〉C2HH〉C1HH. The stability of the penta-coordinated carbonium ions may be explained by the electron distribution in the three-center-two-electron bonds. The delocalization of the penta-coordinated carbonium ion CHC with three-center-two-electron bonds on positive charges was stronger than that of the penta-coordinated earbonium ion CHH with three-center-two-electron bonds and its stability was higher than that of the penta-coordinated carbonium ion CHH with three-center-two-electron bonds.

关键词： n-butane penta-coordinated carbonium ions structure quantum chemical calculation

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畜舍养殖环境智能监控研究现状及展望

华南农业大学学报 2024年第5期45卷 672-684页

作者：付晓魏晓莉严士超戴百生姜润杰周建钊张翼王鑫杰沈维政东北农业大学电气与信息学院黑龙江哈尔滨150030

家畜疫病的发生及传播与养殖环境密切相关,实现畜舍环境信息的精准感知及智能化调控是提高动物健康水平及生产性能的关键,对我国畜牧产业高质量发展具有重要意义。本文从畜舍养殖环境指标体系、精准感知技术与方法、环境优化调控策略及... 详细信息

家畜疫病的发生及传播与养殖环境密切相关,实现畜舍环境信息的精准感知及智能化调控是提高动物健康水平及生产性能的关键,对我国畜牧产业高质量发展具有重要意义。本文从畜舍养殖环境指标体系、精准感知技术与方法、环境优化调控策略及舒适度评估4个方面出发,介绍了影响家畜健康的环境指标、畜舍养殖环境监控设备、无线数据传输优化技术,阐述了环境数据预测模型及分布规律的研究,并重点分析了畜舍调控装备优化设计、多环境参数调控及环境舒适度评估模型等方面的研究和发展现状,最后总结了当前畜舍环境智能监控应用所存在的问题,并对今后养殖环境智能监控发展方向进行了展望,为我国全面发展智慧畜牧业、提升生产效率提供参考。

关键词：畜舍环境智能监控设备精准感知优化调控舒适度评估

Optimization of spatial layouts for underground facilities to achieve carbon neutrality in cities:A multi-agent system model

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Underground Space 2024年第6期19卷 251-278页

作者： Lingxiang wei Dongjun Guo Junyuan Ji Zhilong Chen Huapeng Hu xiaoli Peng Research Center for Underground Space Army Engineering University of PLANanjing 210007China School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China

Subways,underground logistics systems and underground parking,as the primary facilities types of underground,contribute significantly to the achievement of carbon–neutral cities by moving surface transportation to underground,thereby releasing surface space for the creation of more urban blue-green space for carbon ***,in-depth studies on carbon neutrality strategies as well as reliable layout optimization solutions of these three types of underground facilities are *** study proposes a spatial layout optimization strategy for carbon neutrality using underground hydrogen storage and geothermal energy for these three types of underground facilities employing a multi-agent system ***,three spatial layout relationships,competition,coordination,and followership,between five underground facilities that contribute to emission reduction were ***,the implementation steps for optimizing the spatial layout of underground facilities were determined by defining the behavioral guidelines for spatial environment,underground facility,and synergistic ***,using the Tianfu New District in Chengdu City,China,as a case study,layouts of underground facilities under three different underground space development scenarios were simulated to verify the *** findings of this study address the gap in the research on underground spatial facilities and their layout optimization in response to emission *** study provided a significant reference for the study of underground space and underground resources at the planning level to aid in achieving carbon–neutral cities.

关键词： Urban underground space(UUS) Carbon-neutral city Multi-agent system model Underground facility Spatial layouts

Assessment of dairy cow feed intake based on BP neural network with polynomial decay learning rate

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Information Processing in Agriculture 2022年第2期9卷 266-275页

作者： weizheng Shen Gen Li xiaoli wei Qiang Fu Yonggen Zhang Tengyu Qu Congcong Chen Runtao Wang College of Electric and Information Northeast Agricultural UniversityHarbin 150030China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030China

To overcome the shortcomings of traditional dairy cow feed intake assessment model andBP neural network, this paper proposes a method of optimizing BP neural network usingpolynomial decay learning rate, taking the cow’s body weight, lying duration, lying times,walking steps, foraging duration and concentrate-roughage ratio as input variables andtaking the actual feed intake is the output variable to establish a dairy cow feed intakeassessment model, and the model is trained and verified by experimental data collectedon site. For the sake of comparative study, feed intake is simultaneously assessed by SVRmodel, KNN logistic regression model, traditional BP neural network model, and multilayerBP neural network model. The results show that the established BP model using the polynomial decay learning rate has the highest assessment accuracy, the MSPE, RMSE, MAE,MAPE and R2 are 0.043 kg2/d and 0.208 kg/d, 0.173 kg/d, 1.37% and 0.94 respectively. Compared with SVR model and KNN mode, the RMSE value reduced by 43.9% and 26.5%, it isalso found that the model designed in this paper has many advantages in comparison withthe BP model and multilayer BP model in terms of precision and generalization. Therefore,this method is ready to be applied for accurately evaluating the dairy cow feed intake, andit can provide theoretical guidance and technical support for the precise-feeding and canalso be of high significance in the improvement of dairy precise-breeding.

关键词： Cow Feed intake assessment BP neural network Polynomial decay learning rate

一种基于AOP模块相控阵的星载三模宽带圆极化天线

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电子技术应用 2024年第7期50卷 114-117页

作者：康湛毓贺连星费冬亮魏晓黎梁广上海微小卫星工程中心上海201304

设计了一种应用于Ka频段星载相控阵的低成本、宽覆盖、高可靠性的圆极化天线阵元,该阵元通过BGA植球直接与射频前端实现互连,具有差损小、重量轻、成本低的特点,同时基于特征模分析,通过单层微带的超表面设计激励起三模圆极化辐射有效... 详细信息

设计了一种应用于Ka频段星载相控阵的低成本、宽覆盖、高可靠性的圆极化天线阵元,该阵元通过BGA植球直接与射频前端实现互连,具有差损小、重量轻、成本低的特点,同时基于特征模分析,通过单层微带的超表面设计激励起三模圆极化辐射有效地拓展了带宽,克服常规单层微带天线带宽窄的缺点,降低太空高低温环境下天线分层失效的风险,解决现有星载毫米波相控阵阵元低剖面、宽带工作问题。以4个该阵元为一组2×2顺序旋组阵,进一步拓展了阵列天线的工作带宽和轴比带宽,实测了扫描±50°在28~31 GHz轴比小于3 dB,增益曲线随频率保持不变,非常适合在星载Ka频段通信系统应用。

关键词： AOP技术星载相控阵宽带圆极化特征模分析

Predicting the excretion of feces,urine and nitrogen using support vector regression:A case study with Holstein dry cows

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International Journal of Agricultural and Biological Engineering 2020年第2期13卷 48-56页

作者： Qiang Fu weizheng Shen xiaoli wei Yanling Yin Ping Zheng Yonggen Zhang Zhongbin Su Chunjiang Zhao College of Electrical and Information Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Pig-breeding Facilities Engineering Ministry of AgricultureHarbin 150030China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030China National Engineering Research Center for Information Technology in Agriculture Beijing 100097China

Predicting the excretion of feces,urine and nitrogen(N)from dairy cows is an effective way to prevent and control the environmental pollution caused by scaled *** traditional prediction methods such as pollutant generation coefficient(PGC)and mathematical model based on linear regression(LR)may be limited by prediction range and regression function assumption,and sometimes may deviate from the actual *** order to solve these problems,the support vector regression(SVR)was applied for predicting the cows'feces,urine and N excretions,taking Holstein dry cows as a case *** is a typical non-parametric machine learning model that does not require any specific assumptions about the regression function in advance and only by learning the training sample data,and also it can fit the function closest to the actual in most *** evaluate prediction accuracy effectively,the SVR technique was compared with the LR and radial basis function artificial neural network(RBF-ANN)methods,using the required sample data obtained from actual feeding *** prediction results indicate that the proposed technique is superior to the other two conventional(especially LR)methods in predicting the main indicators of feces,urine,and N excretions of Holstein dry cows.

关键词： cow farming pollution feces/urine excretion prediction nitrogen excretion prediction non-parametric model SVR technique

Time Management Skills Gained Whilst Studying Abroad:A Self Reflection

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校园英语 2017年第1期 10-11页

作者： wei xiaoli

*** In 2009 I decided spend a year studying for a Master of Education degree in the *** studied abroad for two years,it is now crucial for me to reflect the ***,this paper aims to highlight the importance of time mana... 详细信息

关键词： time

Grain production space reconstruction and land system function tradeoffs in China

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Geography and Sustainability 2021年第1期2卷 22-30页

作者： Fei Li Zhangxuan Qin xiaolin Liu Zehui Chen xiaoli wei Qiumeng Zhang Min Lei College of Urban and Environmental Science Northwest UniversityXi’an 710127China Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity No.1 Xuefu AvenueXi’an 710127China

Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service *** tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable ***,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair *** results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban ***,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying ***,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban *** can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysi

关键词： Land system function Tradeoffs Synergy Grain production space reconstruction Set Pair Analysis

Effect of Operating Parameters on Composition of Dry Gas Obtained During Gasoline Cracking Process

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China Petroleum Processing & Petrochemical Technology 2010年第3期12卷 1-5页

作者： Sha Youxin Long Jun Xie Chaogang Li Zheng wei xiaoli (Research Institute of Petroleum Processing,SINOPEC,Beijing 100083) Research Institute of Petroleum Processing SINOPEC Beijing 100083 China

The influence of operating parameters on ethylene content in dry gas obtained during catalytic cracking of gasoline was investigated in a pilot fixed fluidized bed reactor in the presence of the MMC-2 catalyst. The results have shown that the majority of dry gas was formed during the catalytic cracking reaction of gasoline, with a small proportion of dry gas being formed through the thermal cracking reaction of gasoline. The ethylene content in dry gas formed during the catalytic cracking reaction was higher than that in dry gas formed during the thermal cracking reaction. The ethylene content in dry gas formed during catalytic cracking of gasoline with a higher olefin content was higher than that in dry gas formed during catalytic cracking of gasoline with a lower olefin content, which meant that the higher the amount of carbonium ions was produced during the reaction, the higher the ethylene content in the dry gas would be. An increasing reaction temperature could increase the percentage of dry gas formed during thermal cracking reaction in total dry gas products, leading to decreased ethylene content in the dry gas. An increasing catalyst/oil ratio could be conducive to the catalytic cracking reactions taking place inside the zeolite Y, leading to a decreased ethylene content in the dry gas. A decreasing space velocity could be conducive to the catalytic cracking reactions taking place inside the shape-selective zeolite, leading to increased ethylene content in the dry gas.

关键词： gasoline operating parameters catalytic cracking dry gas ethylene

Piezoelectric film promotes skin wound healing with enhanced collagen deposition and vessels regeneration via upregulation of PI3K/AKT

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Nano Research 2024年第8期17卷 7461-7478页

作者： Qi Xu Wufei Dai Peizhe Li Qinglin Li Zhen Gao xiaoli Wu wei Liu Wenbo Wang Department of Plastic and Reconstructive Surgery Shanghai Key Laboratory of Tissue EngineeringShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Research Institute of Plastic Surgery Shandong Second Medical UniversityWeifang 261000China Department of Surgery Air Force Medical CenterPLABeijing 100142China

Skin wounds are common in accidental injuries,and the intricacies of wound repair are closely linked to endogenous electric *** stimulation plays a pivotal role in the restorative processes of skin injuries,encompassing collagen deposition,angiogenesis,inflammation,and *** electrical stimulation therapy replicates and enhances the effects of endogenous wound electric fields by applying an external electric field to the wound site,thereby promoting skin wound *** this study,we developed a self-powered repetitive mechanical impacts-electrical stimulation(RMI-ES)system utilizing a BaTiO_(3)/polydimethylsiloxane(PDMS)piezoelectric composite *** to conventional electrical stimulation devices,the fabricated piezoelectric composite film efficiently harvests energy from the pressure applied by the stimulation device and the tensile force occurring during natural rat *** results demonstrated that piezoelectric stimulation generated by the composite membrane expedited the cell cycle,promoting fibroblast ***,piezoelectric stimulation induced favorable changes in fibroblast gene expression,including increased expression of transforming growth factor-β1(TGF-β1),connective tissue growth factor(CTGF),collagen 1,collagen 3,vascular endothelial growth factor(VEGF),and alpha-smooth muscle actin(α-SMA),while reducing interleukin-6(IL-6)*** analysis revealed that piezoelectric stimulation may induce fibroblast migration,proliferation,and collagen expression by influencing PI3K/AKT serine/threonine kinase(AKT)*** confirmation through the addition of the PI3K inhibitor LY294002 validated that piezoelectric stimulation can regulate the repair process after skin injury through the ***,in vivo results demonstrated that the electric field at the wound site effectively promoted wound healing,reduced inflammation,and stimulated collagen deposition and ne

关键词： BaTiO3/polydimethylsiloxane(PDMS)nano-composite membrane piezoelectrical stimulation skin wound healing collagen deposition PI3K/AKT serine/threonine kinase(AKT)signaling pathway