Study on Exergy Analysis of Mine Air-conditioner Using Ice Slurry for Latent Heat Transportation

针对冰浆潜热输送矿井空调系统进行了设计，提出存在峰谷电价下的井上、井下设计方案。以淮南某矿井为例，根据冰浆潜热输送深井空调功能特性，将系统分为一次侧循环系统和二次侧循环系统，采用系统火用平衡分析法，代替传统的能量平衡分析法，得出了冰浆潜热矿井空调系统的火用损失分布

正交匹配追踪和BIC准则的自适应双频段预失真模型优化算法

针对双频段预失真模型复杂度高以及当前的模型优化算法不具有自适应性的问题,提出一种自适应的模型优化算法.采用双频段广义记忆多项式作为预失真模型,通过正交匹配追踪算法对原始模型的基函数项进行排序,每次迭代时用所有已挑选的基函数项构成备选模型,推导了模型输出向量元素服从非独立同分布情况下的贝叶斯信息准则(Bayesian Information Criterion,BIC),并将BIC值最小的备选模型作为优化后模型,从而在原始模型稀疏度和拟合误差门限未知情况下,实现了模型的自适应优化.结果表明:优化后模型与原始模型相比,二者分别预失真后的信号在邻道功率比和归一化均方误差方面均非常接近,预失真效果良好,而模型的系数量减少了75%以上.国家自然科学基金项目(No.61401099);;福建省教育厅项目(No.JAT170087

Strategies of genetic engineering breeding for plant viral resistance

本文简要地介绍了近年来植物抗病毒基因工程育种策略及其机制的研究进展。将植物抗病毒基因工程的策略归纳为3个方面进行了综述,即病毒来源基因、非病毒来源基因和多基因策略。对于各种植物抗病毒基因工程策略介导的抗性主要分为蛋白质和RNA介导的抗性。This paper briefly reviews recent progresses in the strategies and mechanism of genetic engineering breeding for plant viral resistance.The strategies of genetic engineering of resistance to plant viruses are summed up to three aspects,virus origin genes,non-virus origin genes and multiple genes strategies.All kinds of the resistance were labeled into protein-mediated resistance and RNA-mediated resistance.国家“863”计划项目(2001AA241191、2002AA241031);; “948”引进国际先进技术项目(2003-Q06

管棚保护下框架桥顶进工程高程控制分析

大直径管棚保护下直接顶进预制箱涵技术是近年来国内发展起来的一种全新的施工技术,但其难度大,理论发展不完善,可借鉴的经验少.依托南昌市新龙岗大道下穿向莆铁路工程,根据实际工程情况建立力学分析模型,计算框架桥下钢管的受力,并根据钢管的受力情况假定钢管为Winkler弹性地基梁,运用弹性地基梁理论建立钢管挠曲微分方程并求解该微分方程,从而计算出框架桥顶进过程中的钢管挠曲变形,进而确定顶进过程中框架桥高程偏差情况.理论分析表明,底排管棚的支撑和引导作用有助于框架桥推进,并能有效遏制框架桥\"栽头\"和\"抬头\"现象,对于现场工程施工具有很好的参考价值.福建省自然科学基金(2014J01208

Distribution pattern of PAHs in Jiulong River Estuary by both measurement and simulation

于2011年12月(冬季)在厦门九龙江河口及西港采集9个表层海水水样,采用固相萃取—气质联用方法(SPE-GC-MS)分析其中16种多环芳烃含量。研究结果表明,总溶解态态∑PAH含量为157.9~858.0 ng/L。在河口区,随着盐度升高,PAHs含量逐渐降低。基于比值法分析,表明厦门九龙江及西港海域海水中的PAHs来源存在多种途径,呈现混合来源的态势。利用LEVEL III逸度模型研究菲,芘和苯并(a)芘在各介质间的分布以及水——气界面的交换通量。模拟结果与本文实测和文献中的实测值相吻合。在16℃时,三种多环芳烃的大气沉降通量分别为17.38,7.86和8.38μg/day/m2。其中菲在大气沉降中占主导地位,约三分之二。三种多环芳烃的大气沉降通量均随温度升高而减少。当温度高于32℃时,苯并(a)芘开始从水体释放。The concentration of 16 polycyclic aromatic hydrocarbons( PAHs) of nine water samples,collected in the Jiulong River Estuary in December,2011,were analyzed using the SPE-GC-MS method. The results showed that the concentration range of total dissolved PAHs( ΣPAHs) was from 157. 9 to 858. 0 ng / L. The horizontal distribution illustrated that the concentration of ΣPAHs decreased as salinity increased. Based on ratio analysis,PAHs have complicated sources. A Level III fugacity model was developed to simulate the multimedia fate of PAHs and to study the air-water exchange fluxes of three PAHs( phenanthrene,pyrene,benzo[a]pyrene) in the Jiulong River Estuary. The calculated concentration of PAHs was similar to that measured in this study or reported in earlier literature. At 16℃,the net atmosphere deposition fluxes of these PAHs were 17. 38,7. 86 and 8. 38 μg / day / m2. Phenanthrene was predominant in the atmospheric deposition. The net atmospheric deposition fluxes of these PAHs all decreased with tem-perature. When the temperature was above 32. 0℃,benzo[a]pyrene was released from the water into the air.国家自然科学基金(40776044);; 福建省自然科学基金(2012J05078);; 福建省杰出青年科学基金(2014J06014);; 中央高校基本科研专项(20720140507

过渡金属氧化物(M_2O_5)_(m=1,2)~+(M=V,Nb,Ta)与C_2H_4气相反应机理的密度泛函研究

采用密度泛函理论研究了过渡金属钒族氧化物阳离子团簇(M2O5)m+=1,2(M=V,Nb,Ta)与C2H4气相反应机理.反应为(M2O5)m++C2H4→(M2O5)m-1M2O4++C2H4O,反应物先化合生成C—O键相连的化合物,经过过渡态后M—O键断裂,从而发生氧原子转移到碳氢化合物上的反应.对于V2O5+与C2H4的反应,存在经顺式和反式两种过渡态结构路径,从能量上看,经反式过渡态结构的路径更有利.计算结果表明,发生反应时C2H4与钒氧化物阳离子反应大量放热,而与铌、钽氧化物阳离子反应却放热较少甚至不放热,这与实验结果一致.钒、铌、钽氧化物阳离子团簇发生氧转移反应活性不同的原因是金属-氧键的强弱不同所致

过渡金属混合簇Nb_2Rh_2的密度泛函研究

采用密度泛函方法(DFT)研究了过渡金属混合簇Nb_mRh_n(m,n≤2)的结构、稳定性规律及它们的成键情况.结果表明,Nb—Nb键较强,Rh—Rh键较弱,而Nb—Rh键的强度则介于两者之间.在Nb_2Rh_2直线和折线构型中,金属键有强弱交替的现象.Nb_2Rh_2的各种构型在自旋多重度较小时稳定

The most suitable concentration of G418 for sugarcane culture

本试验在农业部甘蔗生理生态与遗传改良重点开放实验室建立的甘蔗再生体系的基础上,在甘蔗愈伤组织培养的不同阶段,分别加入不同质量浓度的G418选择性试剂,以确定用于甘蔗遗传转化筛选的最适浓度.结果表明,G418对各供试甘蔗愈伤组织的抑制作用相似,愈伤组织生长、分化、生根3个阶段的抗性筛选质量浓度分别为20-35、15-35和25 mg.L-1.The study was based on the regeneration system of sugarcane established by Key Lab of Eco-physiology & Genetic Improvement for Sugarcane,Ministry of Agriculture.In the different stages of sugarcane callus culture,they were added into different concentration of G418,in order to ascertain the most suitable concentration of screening in sugarcane genetic transformation.The results showed that the restraining effects of G418 on each six sugarcane callus were similar.The screening concentration of G418 in the growth,regeneration and rootage stages of sugarcane callus were 20-35,15-35 and 25 mg·L~(-1) respectively.国家“863”高新技术研究发展计划资助项目(2001AA241191,2002AA241031);; 948引进国际先进技术项目(2003-Q06)资

Design of pH Control System for Electrodialysis Water Treatment

电渗析技术以其独特优势,在水处理、食品和化工等领域有着广泛的应用。针对电渗析水处理系统出水酸碱度可调的应用需求,利用STM32F407RET6单片机开发了一套基于PID算法的pH值控制系统,运用PWM方式完成了电渗析电源电压的快速控制,实现电渗析水处理系统出水pH值的快速调节,调节时间小于30s。所述酸碱度控制系统的开发,有助于提升水处理系统的响应速度,提高水质监控水平。To meet the requirement of adjustable water pH for electrodialysis water treatment system,a pH value control system based on PID algorithm is developed using STM32F407RET6 microcontraller.Then to realize rapid water pH adjust- ment of the electrodialysis water treatment system,the PWM method is utilized for fast control of the electrodialysis power supply voltage,which makes the adjusting time less than 30s.The development of pH value control system contributes to im- proving the response speed of the water treatment system.国家自然科学基金（51405408）; 厦门南方海洋研究中心项目（15GHS019HJ03）; 厦门市科技计划项目（3502Z20163005）; 福建省中青年教师教育科研项目（JAT160002

ONLINE OBSERVATION FOR UNMEASURABLE INPUTS IN FCCU RISER

［中文文摘］在非线性系统观测理论基础上给出满足一定条件的不可测输入可观性的简化充分性条件 ,在此基础上分析催化裂化提升管反应器 (FCCU)不可测输入的可观测条件 ,提出一更为有效的观测方案 ,给出仿真结果和工业运行结果．［英文文摘］On-line optimizing control of FCCU has been considered as a very important work.Although there have been so many studies on this topic but the practical application results are not so ideal.This is due to essentially th at the process is very complicated so there exist some key input variables which affect the reaction and cannot be measured online.This is the bottleneck of optimization. This paper discusses the problem of on-line observation of unmeasurable variables in nonlinear systems such as FCCU1Based on the theory of nonlinear observers, a simplified sufficient conditon under certain conditons is presented to confirm the observability of the unmeasurable inputs in these systems1Based on it , the observable condition for the unmeasurable inputs in the riser of FCCU is discussed and a more available on2line observation method for these variables isput forward1Simulation results and industrial running results are also given