mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
几种杀菌剂防治辣椒疫病试验初报

对几种国外生产的杀菌剂进行了田间药效试验,结果表明:25%AF-12946SC、53%金雷多米尔-锰锌WG和68%金雷多米尔-锰锌WG这3种杀菌剂对辣椒疫病有很好防效,明显优于国内目前使用的几种同类药剂.
模拟体液法制备纳米级羟基磷灰石

用模拟体液法制备纳米羟基磷灰石(hydroxyapatite,HAP or HA)粉体.研究了反应温度、反应浓度和反应时间对合成的影响.结果发现,制备纳米级羟基磷灰石的最佳工艺条件为:反应温度60℃,浓度为15倍的模拟体液(simulate body fluid,SBF),反应时间为10 h.在此工艺条件下制各的羟基磷灰石粉体的微观形貌为球形颗粒,平均颗粒直径为30 nm.
超磁致伸缩致动器的输出位移与其控制研究

根据自动控制原理，结合磁致伸缩致动器的结构建立了致动器传递函数模型，在此基础上设计了以TMS320C31为核心的致动器位移闭环控制系统。该控制系统主要由硬件和软件两部分组成。进行了致动器位移控制系统的开环实验和闭环实验，实验结果表明，该系统稳定性可靠、精度高，为致动器在实际精密位移控制中的应用打下了基础。
圆柱形状误差的LF模型及其离散辨识方法

本文详细介绍了一种描述圆柱轮廓形状误差几何特征的勒让德／傅里叶模型（LF）。提出了基于勒让德一高斯积分和傅里叶变换相结合的模型参数离散辨识方法，并指出了参数辨识结果的非等精度特性。最后，采用“二次测量法”对所建轮廓模型的合理性，即测量点数的充分性进行判别，并在三座标测量机上进行了实际测量实验验证。
基于GIS的潮流场POM模式计算分析系统

为实现潮流场计算与基于GIS的分析的整体集成，提出了基于GIS的潮流场计算分析系统的总体框架结构，设计了潮流场计算模块、基于GIS的空间分析模块、用户端接口模块与数据库的组织，建立了一个具有基本应用功能的集成系统。选取南海为例进行了潮流计算和基于GIS的结果分析，分析结果验证了该系统的有效性。
铜绿微囊藻生物钟蛋白的表达纯化与抗体制备

为了获得融合表达的铜绿微囊藻（Microcystic aeruginosa）生物钟蛋白KaiA、KaiB、KaiC并制备其相应的多克隆抗体,将kaiA、kaiB、kaiC基因分别克隆到原核表达质粒pET-His中.重组质粒pET-His-KaiA,pET-His-KaiB和pET-His-KaiC经酶切和测序鉴定后,分别转化E.coli BL21（DE3）进行融合表达.经SDS-PAGE分析可知,融合表达的KaiA、KaiB和KaiC蛋白表达量可分别达到菌体总蛋白的25%、40%和20%.经亲和层析后融合蛋白KaiA和KaiB的纯度分别达95%和92%,而KaiC经胶回收纯化后纯度也可达93%.将纯化后的三种Kai蛋白作为抗原分别免疫小鼠制备多克隆抗体,经ELISA检测抗体滴度表明,制备的抗KaiA、抗KaiB和抗KaiC的多克隆抗体效价高,分别可达到1：50000、1：60000和1：100000.Western blotting结果表明：获得的多克隆抗体具有较高的效价,抗体能识别相应的Kai蛋白,具有较高的特异性,能用于铜绿微囊藻生物钟蛋白KaiA、KaiB和KaiC的表达节律检测.
MHTR超临界蒸汽透平循环再热器设计研究

基于采用多堆一机方案可以实现模块式高温气冷堆（MHTR）与大容量超临界蒸汽透平机组的匹配,从而实现MHTR的高效率发电的考虑,进行了MHTR超临界蒸汽透平循环再热器设计的研究.根据百万千瓦级超临界机组的参数确定了主蒸汽和再热蒸汽的MHTR分堆供应方案,给出了再热器的技术参数.通过对不同传热管结构方案的比较,确定了组件式直管型式的结构设计方案,该设计具有结构紧凑、传热系数大、刚度好和制造方便等优点.经过热工水力分析计算,证明这种设计能够满足传热和水动力要求.
基于SSM/I数据的神经网络方法反演海面风速

研究了单参数神经网络（SANN）模型、多参数神经网络（MANN）模型及复合多参数神经网络（CMANN）模型对使用SSM/I数据反演海面风速精度的影响,并对增加85.5GHz垂直和水平极化亮温作为输入项对反演精度的提高进行了验证.重点发展了一种新型的CMANN算法,并分析了它在不同风速范围下的反演效果.随着风速的增加,反演风速的精度也有提高,高风速（≥15m/s）较低风速有更小的风速误差.比较表明,此方法的反演效果优于以往的各种SSM/I反演风速算法.反演风速的范围为0～25m/s,在晴天和云天混合状况下反演风速与实测风速的均方根误差为1.61m/s,晴天则达到1.46m/s.
适用于MC DS-CDMA信号的定时同步算法

提出了一种适用于MC DS-CDMA信号的定时同步方案.该方案针对MC DS-CD-MA系统的特点,通过频域相关器输出矢量旋转同时获得多个同步检测统计量的近似值,既提高了捕获性能,又成倍降低了定时跟踪算法复杂度.理论分析和数值结果证明了方案的可行性.
泡沫Ni-32Cr合金的结构及其性能研究

以聚氨酯泡沫树脂为基体，采用浆料涂覆、电沉积、热解和合金化等技术制备出网状结构的高孔率泡沫Ni-32Cr合金。对该泡沫合金的形貌结构、成分分布和使用性能进行了分析研究。实验结果表明：该泡沫合金骨架平整，成分均匀，相对密度为6．4％，骨架的室温显微硬度HV为168，压缩强度约5MPa，且800℃时氧化1h，其增重率小于2×10^-3。
预镀镍对活性钢热镀锌的影响

研究了四种含硅钢板预镀镍后热浸锌时镀层的生长动力学，以及镀层中合金相的形成和生长规律，探讨了预镀镍对活性钢热浸锌镀层生长的抑制机理。实验结果表明；预镀镍法可以显著降低活性钢镀锌层的快速生长，获得厚度适宜、表面光亮，粘附性好的镀层。预镀镍钢板热浸锌时首先形成一系列的Ni-Zn合金γ’，γ和δ2相，随着进一步的扩散和反应，γ’，γ和δ2相逐渐消失，生成了Fe-Zn-Ni三元金属间化合物Γ2和Fe-Zn金属间化合物Γ和δ；随后Γ2相消失，在δ相和液相Zn间生成块状的ζ晶粒，并逐渐变成稳定致密的连续ζ层。钢板预镀镍后热镀锌时完全改变了Fe-Zn相的生长顺序，明显延缓了ζ相的生长，显著抑制了活性钢热浸镀锌层的异常生长。
多层吸波材料的电磁参数反演

提出了一种可以通过多层吸波材料的反射系数和传输系数来推导其等效材料的介电常数εeff和磁导率μeff的方法。等效εeff和μeff是与多层吸波材料具有相同反射系数和传输系数的单层均匀材料的电磁参数。引入等效εeff和μeff可以极大简化吸波材料的分析和设计。计算或测量得吸波材料的反射系数和传输系数后，由本工作给出的公式可以方便地求出等效εeff和μeff。
PA封端对ODPA／ODA聚酰亚胺薄膜热稳定性的影响

制备了经邻苯二甲酸酐（PA）封端的理论数均分子量为10000和30000的聚酰亚胺（PI）薄膜，通过差示扫描热分析（DSC）测定薄膜高温热处理前后玻璃化温度的变化，研究了PA封端对ODPA／ODA聚酰亚胺薄膜热稳定性能的影响。结果表明，封端可有效阻止分子链的无序增长，使聚酰胺酸（PAA）分子量分布变窄;且可明显减少分子链在高温下的反应，表现为热处理前后封端薄膜Tg变化明显小于未封端的薄膜。随着高温热处理时间的延长，短链薄膜Tg增长趋势减缓，长链薄膜的Tg变化直线上升。从高温再聚合、交联反应和端基活动性出发，解释了Tg升高和PA封端有利于提高PI薄膜热稳定性的原因。
Extraction Phase Simulation of Cargo Airdrop System

To study the characteristics of cargo extraction, the initial phase of airdrop process, a high fidelity and extendibility simulation model with uniform motion equations for all states during extraction is developed on the basis of dynamics methods and contact models between cargo and aircraft. Simulation results agree well with tests data. Cargo exit parameters, which contribute to cargo pitch after extraction, are studied. Simplified computation model of dimensionless exit time is developed and used to evaluate the relation between extraction phase and landing accuracy. Safe interval model is introduced to evaluate the safety of extraction process. Also,relations between initial parameters, including pull coefficient, aircraft pitch and CG coefficient, etc, and result parameters, including exit time, cargo safety, pitch, ete, are developed to help design of airdrop system. especially the selection of extraction parachute and cargo deployment.
生长调节物质对黑果腺肋花楸试管苗增殖和生根的影响

研究了不同种类植物生长调节物质对黑果腺肋花楸试管苗增殖和生根的影响，结果表明：KT对黑果腺肋花楸试管苗的增殖无效果；MS＋0．5mg／L6-BA＋0．2mg／LIBA对黑果腺肋花楸试管苗的增殖、继代培养效果最好；IBA的生根效果优于NAA，尤其是1／2MS＋0．4mg／LIBA表现最好。
标准样地在耕地后备资源开发适宜性评价中的应用研究

运用河北省农用地分等成果,探讨标准样地在耕地后备资源评价中的应用,提出了用“4层控制”及限制性指标作为控制层,用标准自然质量分与后备资源自然质量分相减,得到后备资源开发潜力分,根据开发潜力分确定开发级别,最终确定耕地后备资源开发适宜性程度.
冬小麦、夏玉米品种搭配及氮磷钾统筹施肥技术研究

为提高冬小麦、夏玉米全年总产和肥效，试验在全年N、P、K肥施用总量分别为630、296、302kg／hm^2的情况下，探讨了上下茬配额及品种搭配对全年总产量的影响。4因子裂区设计，主处理为上下茬品种搭配，副处理、副副处理及次副副处理分别为N、K、P在上下茬的分配比例。品种搭配、K处理、N×P、N×P×K对年总产作用极显著，P处理、品种搭配×P×K作用显著。石新733与郑单958搭配，N平均分配，冬小麦施2／3的PK肥、夏玉米施1／3，是获取全年高产的最优方案，并突破了19500kg／hm^2。N、P、K上下茬平均分配、或小麦均施2／3、或玉米均施2／3，都不利于全年高产。
低温胁迫对青榨槭幼树抗寒指标的影响

以3年生青榨槭幼树1年生枝条为材料，测定了不同冷冻处理条件下细胞超氧化物歧化酶（SOD）和过氧化物酶（POD）活性、丙二醛（MDA）含量以及枝条的相对电导率。结果表明：随着温度下降，细胞SOD和POD酶活性均呈现先升高后下降的趋势，MDA含量随温度降低逐渐升高；枝条相对电导率随处理温度降低呈“S”形上升。相对电导率结合Logistic方程推算的青榨槭低温半致死温度（LT50）为-29．93℃，与枝条恢复生长试验结果基本一致，因此，相对电导率可以作为测定青榨槭低温半致死温度简洁、有效的生理指标。
土壤干旱对冬小麦幼苗生理特性的影响

采用盆栽试验对不同土壤干旱条件下冬小麦幼苗生理特性进行了研究。结果表明，幼苗叶片叶绿素a、叶绿素b、叶绿素总量、光合速率、蒸腾速率、气孔导度、株高、叶面积、叶干重、茎干重、根干重、总生物量，均随土壤水分的减少而呈降低趋势；叶片水分利用效率和根冠比均呈增加趋势。通过回归分析发现，冬小麦幼苗叶片光合速率、蒸腾速率、气孔导度和WUE与土壤水分之间，均存在极显著线性关系。以上研究结果说明，土壤干旱对冬小麦幼苗光合特性、蒸腾特性、气孔导度、WUE及生长特征具有重要影响。
北京鹫峰地区松栎混交群落结构与物种多样性

利用在北京鹫峰地区设置的8个样方的调查资料，对该地区松栎混交群落结构及物种多样性进行了分析研究。结果表明：群落土壤呈微酸性，自然肥力较低；调查共计维管束植物58种，隶属于36科56属，其中乔木树种占主导地位，植株的最大密度为1975株／hm^2；生活型谱以高位芽植物最多，1年生草本植物比例居中，反映出群落水分条件一般；群落结构分明，乔木层、灌木层和草本层层次清晰；乔木以栓皮栎占绝对优势，其重要值最高，优势度明显；乔木层物种多样性指数不高，群落物种丰富度和多样性指数主要受灌木层和草本层影响，群落处于恢复前期；群落的物种丰富度、物种多样性指数和均匀度指数反映出基本一致的趋势，不同层次的Shannon-Wiener多样性指数、Simpson优秀度指数、种间相遇机率和Pielou均匀度指数的趋势基本上是草本层〉灌木层〉乔木层。
野芙蓉叶片解剖结构与其抗旱性关系的研究

利用石蜡切片法对野芙蓉[Abelmoschus manihot（Linn.） Medicus]的叶片进行形态解剖学研究.结果表明：野芙蓉叶片的解剖结构与其抗旱性之间有着密切的相关性,与同科的植物苘麻和蜀葵相比较也证实了其抗旱的结构特点.
八达岭森林健康示范区森林火险等级区划的研究

针对八达岭森林健康示范区森林火灾发生特点与规律, 选取海拔高度、郁闭度、经营措施、距旅游点的距离、优势树种、林道距离6个影响林火发生较大的因子,运用聚类分析的方法,对八达岭森林健康示范区的121个小班进行了森林火险等级区划,把森林健康示范区分成3个火险等级区,通过实际调查,分类小班和实际情况较一致,为林业部门进行森林火灾管理提供有价值的参考,从而达到防灾减灾,保护森林资源的目的.
利用CTAB法提取红掌不同部位基因组DNA

采用CTAB法,对红掌的叶、叶柄、肉穗花序、佛焰苞、根等5个部位进行基因组DNA提取,利用紫外分光光度法、琼脂糖凝胶电泳法和RAPD扩增法检测DNA的质量,结果表明,CTAB法适合红掌根和叶的基因组DNA提取,没有蛋白质、酚及色素等杂质的污染,佛焰苞的DNA中有少量蛋白质污染,叶柄DNA中含有较多的蛋白质、酚等杂质,而从肉穗花序中没有提取到基因组DNA.
杏花器官抗寒性初步研究

以杏盛开花朵为试材,利用人工模拟霜箱,对花器官抗寒性进行了研究.结果表明：杏花器官的过冷却点为：花瓣-4.0～-5.2℃,雄蕊-3.3～-4.1℃,雌蕊-2.8～-3.2℃.低温胁迫条件下,杏花器官褐变程度加剧,相对电导率增高,质膜透性增强,膜保护酶SOD、POD的活性在低温胁迫前期均逐渐升高,在达到一定的临界低温后,呈现下降的趋势.花器官抗寒性表现为花瓣〉雄蕊〉雌蕊,品种间抗寒性有差异.
钙对东方百合生长和开花的影响

采用室内光照砂培盆栽培养试验,研究钙营养对东方百合生长和开花的影响.结果表明：在10月23日（出苗32 d）现蕾以前,缺钙处理与加钙处理对植株生长无显著差异;但从10月23日（出苗32 d）现蕾开始,2处理植株生长差异显著,缺钙处理植株同加钙处理的相比,表现为植株生长缓慢,花蕾脱落,植株矮小,开始出现叶烧现象,而后叶烧越来越严重.从11月22日（出苗62 d）蕾膨大开始,缺钙处理植株的根冠比显著高于加钙处理;植株生物量显著低于加钙处理.供应钙从10月23日（出苗32 d）现蕾开始,对百合生长是有利的,可以减少叶烧的发生,同时改善百合切花的品质.
农杆菌介导法将LFY基因导入苹果的研究

以M26苹果叶片为外植体,利用GUS瞬时表达率,对农杆菌介导法转化苹果的因素进行优化,通过含LFY基因的根癌农杆菌EHA105转化苹果叶片,获得了提早开花的转基因植株.结果表明：以OD600=0.3～0.5农杆菌菌液侵染叶片,25℃条件下共培养,共培养后的叶片延迟筛选3 d,在附加卡那霉素30 mg/L的再生培养基中选择培养,转化芽再生率可达6.97%.PCR检测初步证明目的LFY基因已整合到苹果基因组中.
海水养殖废水灌溉条件下SPAC系统中水盐肥通量研究

2004年4月～10月,在半湿润的莱州地区布置蒸渗试验,研究海水养殖废水灌溉条件下SPAC系统水盐肥通量.试验设5个处理,分别为CK(种作物,不灌溉)和淋洗分额(LF)为0.1、0.2、0.3、0.4的海水养殖废水灌溉处理.结果表明:对于淋洗分额为0.1、0.2、0.3、0.4的海水灌溉处理,用于土壤蒸发和作物蒸腾的海水养殖废水量分别占菊芋生育期总蒸散量的36.5%、36.2%、37.0%、37.3%;对于上述海水养殖废水灌溉处理,土壤耕层的盐分积累量分别为91.1、94.1、98.7、107.1 g;而铵态氮的积累量分别为2.00、2.29、2.27、2.82mg,硝态氮的积累量分别为1.81、1.40、1.29、0.92mg,活性磷酸盐的积累量分别为3.03、2.68、2.44、1.67 mg.因此,认为海水养殖废水灌溉在供给作物水分和养分方面起到积极作用,但需采取调控措施以防耕层土壤盐分过量积累.
红壤性水稻土施肥的产量效应及与气候、地力的关系

以23 a红壤性水稻土化肥定位试验为对象,探讨了不同施肥措施下水稻产量变化及其与气候、地力的关系.结果表明:不同施肥措施的产量效应均显著受气候的年成变化及其交互作用的影响,气候的季相变化因不同施肥措施而异,对CK、NK、NPKM处理影响不大,而对N、NP、NPK处理有强烈的影响;红壤性水稻土基础地力贡献率较稳定,为46.3%～72.0%.随着施肥结构完善,对地力贡献的依赖性表现出NPKM
淹水土壤有机酸积累与秸秆碳氮比及氮供应的关系

有机酸积累和毒害是稻田秸秆还田中受到广泛关注的问题.本文以水稻与小麦秸秆为材料,采用淹水培养研究了甲酸、乙酸、丙酸及丁酸在土壤中的积累及其与秸秆碳氮比、氮肥添加量的关系.结果表明,在不施用氮肥的情况下,随秸秆用量的增加,秸秆处理的有机酸积累均显著增多.与稻秸处理相比,麦秸处理的有机酸(尤其是丙酸)积累量显著较高,土壤溶液中NH_4~+浓度显著较低.加入尿素明显减少有机酸积累,促进CH_4排放,但对CO_2的排放无显著影响;氮素的影响在麦秸处理中表现的尤为明显.上述结果说明麦秸的高碳氮比增加了无机氮的生物固定,抑制有机酸向CH_4转化,从而导致麦秸处理有机酸积累量高于稻秸处理.施用氮肥是减少麦秸还田后有机酸积累的有效措施之一,但此措施将可能促进CH4的排放.
杭嘉湖地区水稻土中氟的分布特征

测定分析了杭嘉湖地区400余份水稻土土样中氟(全氟、交换态氟和水溶态氟)的含量,对该地区水稻土中氟的土壤环境质量评价基准值进行了初步研究.结果表明,水稻土中的全氟与可交换态氟含量均呈正态分布,水溶态氟的含量符合对数正态分布.在5种不同母质发育的水稻土中,河相沉积物发育的水稻土全氟含量最高,算术平均值为333.1 mg kg~(-1);海相沉积物发育的水稻土次之,为324.3 mg kg~(-1);黄壤和红壤性坡残积物最低,为245.4 mg kg~(-1).海相沉积物发育的水稻土水溶态氟和可交换态氟含量最高,分别为1.55 mg kg~(-1)和4.03 mg kg~(-1).不同类型的水稻土(渗育性水稻土、潴育性水稻土、潜育性水稻土和淹育性水稻土)剖面中耕作层的全氟含量均高于亚耕层,而剖面中水溶性氟的分布规律则相反.初步确定杭嘉湖地区水稻土中氟的环境质量评价基准建议值全氟为413.9 mg kg~(-1),水溶态氟为2.54 mg kg~(-1).
基于ArcGIS的彭水县烟区土壤有效态微量元素丰缺评价

研究基于ArcGIS技术,应用地统计学方法对彭水县烟区土壤微量元素丰缺状况进行了评价.结果表明:研究区域土壤微量元素中,有效铜、有效铁及有效锰的样本呈正态分布,其他微量元素为偏态分布,其变异系数在29.47%(有效钼)～51.76%(有效铁)之间变化;土壤有效铜、有效硼、有效铁和有效锰的样本数据最佳拟合模型为球状模型,有效钼和有效锌为指数模型;土壤微量元素的随机变异均小于结构性变异,有效铜、有效硼、有效钼及有效锌的空间自相关性相对较弱,有效铁及有效锰则具有较强的空间自相关性;有效铜、有效锰、有效硼含量偏低,有效钼、有效铁及有效锌含量丰富.
华北潮土长期试验中的作物产量、氮肥利用率及其环境效应

在河南封丘潮土上进行了小麦、玉米轮作的长期肥料试验,对该长期试验的作物产量、氮利用率及其环境效应进行了分析.结果表明,在施氮量为150kg hm~(-2)季~(-1)的情况下,化肥N、P、K配合施用(NPK),小麦和玉米产量最高,且年际之间变化小,14 a平均产量分别为5 261 kg hm~(-2)和7 633 kg hm~(-2).在等N、P、K的情况下,1/2氮用有机肥(1/2OM),作物产量略低于NPK;全部氮用有机肥(OM),平均产量分别降低22%和16%,产量年际变化大,但表现出随时间而提高的趋势.小麦和玉米氮肥平均利用率NPK分别为60%和61%、1/2OM为51%和56%,OM为33.6%和42.5%.上述处理的表层土壤(0～20 cm)全氮含量均显著增加,增加幅度依次递增;作物吸收和表层土壤残留氮合计占氮肥施用量的69%、75%和69%,均未发现NO_3~-盐向土壤剖面深层的移动,N_2O的排放系数＜0.24%.不施P肥的处理(NK),作物产量极低,氮肥利用率几乎为零,且有大量的NO_3~-向剖面深层迁移,在0～100cm范围内,NO_3~-含量随着深度的增加而提高,但N_2O排放系数小于上述3处理.由此可以得出,在该土壤上采用小麦、玉米轮作,年氮施用量300kg hm~(-2),如果配合P、K肥,可以持续保持较高的产量,且不造成NO_3~-盐淋移和大量N_2O排放.
基于高分子乳化剂的共聚物流变行为及稳定性

考察了高分子乳化剂和小分子乳化剂共混使用对共聚物乳液流变行为和稳定性的影响规律.利用VT550旋转黏度仪研究了基于高分子乳化剂(聚乙烯醇)的丙烯酸丁酯/苯乙烯/丙烯腈三元共聚物乳液的流变特性,并分析了乳液的耐电解质(CaCl_2)稳定性.实验结果表明,随着温度升高,共聚物的表观黏度下降,流动指数增大,体系黏度特性逐渐由假塑性流体向宾汉塑性流体转变.高分子乳化剂的加入明显增加了乳液体系的黏度,使得乳液流动指数增大,体系的耐电解质稳定性也大幅度提高.
紫外扫描式水质COD测量技术与仪器研制

介绍了一种基于紫外全波段扫描的水质化学需氧量(COD)测量技术以及运用该技术设计开发的在线COD测量仪器.该仪器采用嵌入式微机系统实时采集与计算由紫外分光扫描系统得到的多个紫外吸光度,运用反相传播(BP)神经网络建立紫外吸光度和COD的数学模型.在实际使用时利用该模型的Levenberg-Marquardt快速算法,根据实际水样的吸光度值可以快速推算出水样的COD值.实验结果表明,该COD测量仪器具有测量精度高、无二次污染等特点.
以乙酰丙酸为原料合成5-羟基乙酰丙酸的研究

对新型聚酯单体5-羟基乙酰丙酸(5-HLA)的合成工艺进行了改进和优化.以来源于生物质资源的乙酰丙酸(LA)为原料,通过改进的溴化和水解反应合成了5-HLA.优化溴化反应温度、液溴滴加速率、反应介质用量等溴化反应条件;同时利用3-溴乙酰丙酸甲酯等溴化物的分子内重排和歧化反应,对溴化反应生成的副产物回收再利用,将中间产物5-溴乙酰丙酸甲酯的产率从文献值30%提高到45%.5-溴乙酰丙酸甲酯经一步水解、乙醚连续萃取和重结晶得到5-HLA.改进后的工艺基于乙酰丙酸的产率为30%,与二步法相比,操作时间短,产率大大提高.
非数控设备集群监测制造的实现方式研究

提出一种基于非数控机械制造设备的设备集群监测制造的生产组织方式,并借助实验研究了获取制造设备主要信息的实现方法.借助此法,工艺与管理人员可以获取多种有益于指导生产的信息.
纤维缠绕管道变速比段控制算法研究

为了保证缠绕控制精度不受芯模速度波动的影响,研究了变速比段的自适应控制算法.根据缠绕纤维均匀布满芯模表面的要求,研究了落纱点与芯模在纱车变速比段需要满足的速度和位置边界条件,建立了落纱点和纱车之间的运动数学模型,并且通过待定系数法得到了纱车运动控制算法.经仿真实验验证,该算法的控制精度不低于0.05 mm.
三角形强化栽培技术对水稻光合生理特性及产量形成的影响

以杂交水稻冈优527为材料,研究了水稻在三角形强化栽培、正方形强化栽培、抛秧栽培和常规高产栽培等不同栽培方式下的生理指标、灌浆特性及产量.结果表明,在三角形强化栽培技术体系下适宜密度的水稻群体具有独特的优势: 在关键生育时期叶面积指数(LAI)较大,齐穗后剑叶衰老减缓,光合速率较高,能够充分 发 挥个体生长优势,贮存积累并向穗部转运较多的光合同化产物,不仅保证了强势粒的灌浆, 而且弱势粒灌浆也较为顺畅,产量构成因素得到优化配置,从而获得高产.
早熟抗稻瘟病籼型水稻不育系荣丰A的选育与利用

荣丰A是广东省农科院水稻研究所用优IB/博B的F_4代优良株系与优IA测交并连续回交转育而成的早熟抗稻瘟病籼型不育系,2005年10月通过广东省技术鉴定.荣丰A表现株型紧凑,不育性稳定,配合力强,抗稻瘟病,柱头外露率高 ,异交结实率高,对"九二○"敏感,易于繁制种.利用该不育系初步测配出杂交早稻荣优 2号、荣优3号和荣优4号,在区试和试种中均比对照增产.
中国杂交水稻发展现状分析

根据全国农业技术推广服务中心每年提供的"全国农作物主要品种推广情况统计表"的数据,分析了中国杂交水稻在过去15 a(1990-2004年) 的发展状况和规律,包括不同不育系的系列组合的数量和种植面积的变化情况,讨论了今后中国杂交水稻可持续发展的趋势和方向.
物理-化学法处理桑皮脱胶废水的研究

桑皮纤维是一种资源可再生纤维素纤维,但在脱胶制取桑皮纤维过程中产生大量的废水,污染环境,限制了桑皮纤维的开发利用.采用调节pH值、絮凝、Fenton试剂催化氧化、活性炭吸附等物理-化学综合处理法处理桑皮脱胶废水,研究结果表明,通过物理化学法处理桑皮脱胶废水,COD总去除率达到97%以上,色度降到5倍.此方法处理效果明显、操作简单.
水稻抗倒伏研究进展

倒伏是水稻生产中的一个严重问题.从水稻倒伏的主要影响因子、水稻抗倒伏机理、抗倒性评价及其遗传等方面,综述了水稻抗倒伏研究进展 ,提出了有待拓宽和深化研究的内容.
城市旅游区暴雨径流污染过程中的不透水面效应

选取武汉市动物园4种典型的不透水面暴雨径流污染特征进行了系统的研究,以期为旅游区面源污染危害评价和治理提供基本的依据.结果表明,动物园4种不透水面初期径流污染物浓度很高,COD最大值达1140 mg/L,下垫面类型及地表累积污染物是影响径流水质的主要因素.通过无量纲累积曲线的分析,表明旅游区不透水面径流初期冲刷严重,该曲线还为面源治理提供了重要的工程参数.
高温气冷堆氦气轮机性能的初步研究

结合了模块式高温气冷堆与气体透平循环技术的高温气冷堆氦气轮机循环是核电领域中的全新概念,为高核电的安全性和经济性提供了新思路,具有很强的竞争优势.首先对高温气冷堆氦气轮机进行了初步研究,表明氦气轮机叶片级数多,叶片高度低.然后应用商业软件NUMECA对平面叶栅在相同的进出口条件下分别以氦气和空气为工质进行了二维数值模拟计算,并进行了流场分析,揭示了氦气轮机与燃气轮机的区别.
烟气再循环对液雾旋流火焰的影响

在柱状燃烧室内利用Canon数码相机跟踪研究了气泡雾化喷嘴出口下游的旋流液雾火焰,发现再循环烟气对油雾颗粒的预热作用使火焰缩短、并有效削弱了高温区存在;利用Testo350烟气分析仪对液雾旋流火焰所产生的烟气成分进行了测定,探讨了烟气再循环措施对不完全燃烧产物以及燃烧污染物生成量的影响,发现热烟气的再循环可以有效降低不完全燃烧产物的排放量,同时可以抑制NOx的生成.
微生物燃料电池在污水处理中的研究进展

微生物燃料电池(microbial fuel cell, MFC)利用微生物催化剂将其代谢能直接转化为电能,具有原料广泛、反应条件温和、清洁高效等优点.简述了MFC的工作原理及分类,总结了用于污水处理的MFC的性能及其影响因素.探讨了MFC在实际应用中的瓶颈,并展望其在污水处理中的应用前景.
Modeling of temperature-humidity for wood drying based on time-delay neural network

The temperature-humidity models of wood drying were developed based on Time-delay neural network and the identification structures of Time-delay neural network were given. The controlling model and the schedule model, which revealed the relation between controlling signal and temperature-humidity and the relation between wood moisture content and temperature-humidity of wood drying, were separately presented. The models were simulated by using the measured data of the experimental drying kiln. The numerical simulation results showed that the modeling method was feasible, and the models were effective.
The impact of tourism on soils in Zhangjiajie World Geopark

The soil hardness, soil water content and soil bulk density along the trails of six scenic spots in the Zhangjiajie World Geopark were measured and analyzed, and the integrated effects of tourism trampling on soils were evaluated for each scenic spots by calculating its soil impact indexes (SII) in the park. The results indicated that visitors' activities caused a serious influence on the soil in the park, especially in the two most used scenic spots-- Yellowstone Village and Gold Whip Stream. The impact of tourism on soil mainly occurred within 3 m along the trails. The impact shapes are classified into six type as single-sided node type, double-sided node type, cross node type, single-sided linkage type, double-sided linkage type and short-cut linkage type. Of six types of impact shapes, the single-sided node type and double-sided type were dominant. The average water contents of soil for six scenic spots at sample areas of 1 m, 2 m and 3 m from trial is 36.6%, 24.5% and 2.2% lower than that of the control area, respectively. The average soil hardness for six scenic spots at 1m, 2 m, and 3m from the trails tramped increased 167.9%, and 122.2%, and 15.8%, respectively, compared with the control area. Soil bulk density increased 26.5% at 1 m and 20.9% at 2 m from the trails. The main countermeasures for reducing the range and extent of tourism impact on soil are discussed.
Economic profitability of cane based furniture enterprises of Chittagong City Corporation Area, Bangladesh

An exploratory survey was conducted to assess economic profitability of cane based furniture enterprises in Chittagong City Corporation area of Bangladesh. A multistage random sampling was adopted to carry out the study. Based on the total investment the enterprises were divided into large, medium and small.. Most of the entrepreneurs (55%) are in the age class 40-50 years and only (18.33%)are ＞50 years. In small and medium category lowest entrepreneurs (8.33% each) are found graduate and 18.33% in large farm. Most of the enterprises are in the small category (45%) and 66.67% labors are skilled whereas only 33.33% are unskilled. Seven articles of sixteen different sizes were identified made from cane, which are Sofa (45 cm × 45 cm, 50 cm × 50 cm and 55 cm × 55 cm), Dinning (4ch. 1tab,and 6ch. 1tab.), Bed (1 m × 2m, 1.3 m × 2.3 m and 1.5 m × 2.3 m), Chair (45 cm × 45 cm and 50 cm ×50 cm), Rocking chair (large size,medium and small size), Dolna (Hanging and Running) and Partition. In all the three category enterprises chair (45 cm × 45 cm) was produced in highest number and the lowest production was Bed (1.5 m × 2.3 m). The total net benefit (2089 US
Rheological properties of low consistency TMP from thinning wood of Chinese Fir

The rheological behavior of low consistency thermomechanical pulp of Chinese fir harvested by intermediate thinning was analyzed. The results show that the apparent viscosity of pulp changed along with the beating degree, pulp consistency and shearing velocity. With the increasing of pulp consistency, the apparent viscosity of pulp increased gradually. Beating degree of pulp had an effect on microstructure of pulp. The apparent viscosity of pulp declined as beating degree of pulp increased, and the apparent viscosity of pulp fell along with the shearing velocity increasing. Based on the results, the rheological models are set up. The models showed that the fluid types of the low consistency pulp could be described as pseudoplastics fluids (non-Newtonian fluids).
Distributional patterns of species diversity of main plant communities along altitudinal gradient in secondary forest region, Guandi Mountain, China

Fourteen plots were chosen along with the altitude of 1600-2600 m in Guandi Mountain, Shanxi Province, China to investigate all the trees in the plots, and the species diversity indexes were calculated for analyzing the effects of altitudinal gradient on plant species diversity. The results showed that the order of dominant species from low altitude to high altitude is as Quercus liaotungensis Koidz, Pinus tabulaeformis, Betula platyphylla, B. albo-sinensis, Picea wilsonii, P. Meyeri and Larix principis-rupprechtii. With altitude increasing, the average height and DBH of the arbor firstly increase and then decrease, the maximal height and DBH of the arbor present the unimodal variable trend, the maximal height of coniferous and broad-leaved trees firstly increases and then decreases, the maximal DBH of broad-leaf trees has no clear fluctuation, and the maximal DBH of the needle-leaf trees decreases gradually. Moreover, in middle altitudinal communities (the altitude of 1900-2200 m), the maximal height and DBH of the needle-leaf trees are larger than these of broad-leaf trees. Both Shannon-wiener index and Margalef index of the communities present the unimodal variable trend, with a peak in the mid-altitude. Plant species diversity in the mid-altitude (1900-2200 m) is higher than that of the low altitude (1600-1900 m) and the high altitude (2200-2600 m). In addition, the unimodal variable trend of α species diversity is clearly correlated with the altitudinal gradient. The change of plant species diversity is significantly correlated with the altitudinal gradient, and also related to the community structure, the community composition, the feature of species and the human disturbance.
A modified one-step procedure for rapid RNA isolation from insect

A modified guanidinium isothiocyanate method was used to extract total RNA from two forest insect species Clostera anastomosis and Saperda populnea. The integrity of RNA was demonstrated by the methods of gel electrophoresis and cDNA analysis. Typical A260/ A280 absorbance ratio of the total RNA was in range of 1.8 to 2.0. The size of double strand cDNAs obtained by RT-PCR was more than 2 kb, which indicated that intact mRNA was obtained. The fragments of β-actin and chitinase gene from the RNA of C. anastomosis were obtained by RT-PCR, which indicated that the RNA could be used for other molecular operation. By this procedure, RNAs could be extracted and analyzed by electrophoresis from at least 8 samples within 4 hours. These results showed that this method was time- and cost-saving and effective.
Spatio-temporal distribution of net primary productivity along the northeast China transect and its response to climatic change

An improved Carnegie Ames Stanford Approach model (CASA model) was used to estimate the net primary productivity (NPP) of the Northeast China Transect (NECT) every month from 1982 to 2000. The spatial-temporal distribution of NPP along NECT and its response to climatic change were also analyzed. Results showed that the change tendency of NPP spatial distribution in NECT is quite similar to that of precipitation and their spatial correlation coefficient is up to 0.84 (P < 0.01). The inter-annual variation of NPP in NECT is mainly affected by the change of the aestival NPP every year, which accounts for 67.6% of the inter-annual increase in NPP and their spatial correlation coefficient is 0.95 (P < 0.01). The NPP in NECT is mainly cumulated between May and September, which accounts for 89.8% of the annual NPP. The NPP in summer (June to August) accounts for 65.9% of the annual NPP and is the lowest in winter. Recent climate changes have enhanced plant growth in NECT. The mean NPP increased 14.3% from 1980s to 1990s. The inter-annual linear trend of NPP is 4.6 gC·m-2·a-1, and the relative trend is 1.17%, which owns mainly to the increasing temperature.
Effect of microbial inoculants on Albizia saman germination and seedling growth

Microbial Inoculants as Effective Microorganisms (EM) were applied to find out their effects on germination and seedling growth of Albizia saman in the nursery. The seedlings were grown in a mixture of sandy soils and cow dung (3:1) kept in polybags. The EM solution at different concentrations (0.1%, 0.5%, 1%, 2%, 5% and 10%) was incorporated before and after a week of sowing seeds. Germination and physical growth parameters, including shoot and root length, vigor index, collar diameter, leaf number, fresh and dry weight of shoot and root and total biomass increment over the control were measured. The nodulation status influenced by EM was also observed along with the estimation of chemical parameters like chlorophyll a, chlorophyll b and carotenoid. Both germination and the measured physical growth parameters were found significantly (P<0.05) higher in seedlings treated with different concentrations of EM solution in comparison to the control. Maximum growth was found at 2% followed by 1% EM solution. Nodulation was higher at 0.1% concentration but it normally decreased with the increase of concentrations. Although there were a higher amount of pigments in leaves of the treated seedlings than of the control, the variations recorded with respect to chlorophyll a, b and carotenoid were not significantly higher in most of the treatments. Treated seedlings showed variable results along with the increment of EM applications and most of the parameters showed best results at the medium range of concentrations. The study indicates that the Microbial Inoculant (EM) technology might be useful to improve the growth of seedlings in the nursery. This also indicates that the associated beneficial organisms along with the polybag soils might be of value in improving the degraded soil or poor field soil for better nutrient and water uptake during the initial growth of transplanted seedlings.
Forestry ecological footprint in China during 1973-2003

The ecological footprint (EF) model has received much attention as an assessment indicator for sustainable development in recent years. Firstly, the temporal changes of domestic timber production, imports and exports in China were analyzed from 1973 to 2003, the analysis results showed an apparent fluctuation in timber production during 1973-1995 but a decreasing trend during 1995-2002, an increasing trend in timber imports since 1995 especially after the implementation of the Natural Forest Protection Project (NFPP), an decreasing trend year by year in timber exports since 1995. Secondly, this paper presented a time series analysis of actual forest area demand in the sustainable yield and production approach in China from 1973 to 2003, which includes both import and export forest area demand. The results showed the actual forest area demand simulated from the sustainable yield approach was slightly higher than that from the production approach during 1978-1988 and a little lower during 1989-2003; however, the actual forest area demands simulated by these two model approaches were larger than calculations that expressed in conventional forest EF. Meanwhile, the results indicated the forestry development in China during 1978-1988 was unsustainable due to overexploitation of forest stocking volumes, and China's forestry moved toward sustainable development since 1989 because forest resources are exploited at lower rates than they are regenerated. However, compared to forestry developed countries, the forestry development capacity in China is still lower. Finally, based on the model results we analyzed the relationships between forestry EF and the key policies, including trade policy, economic policy and forest conservation programs. In addition, several suggestions about reducing forestry EF and enhancing sustainable forestry development in China are given.