油茶轻基质无纺布容器育苗技术

在常规的油茶芽苗砧嫁接育苗技术基础上,初步探索了油荼轻基质无纺布容器育苗技术.结果表明,采用轻基质无纺布容器育苗技术,一年生油茶嫁接成活率可达85.7％,苗木合格率可达到93.4％,其中Ⅰ级苗62.7％,Ⅱ级苗30.7％,当年可出圃.结合使用特定的育苗托盘,可有效减少育苗工序,降低育苗成本.该技术可操作性强、成活率及出...     

低循环风速下木材表层水分蒸发的试验研究

木材干燥过程中,介质循环速度是一个影响木材干燥的重要工艺参数.在木材各含水率阶段,通过试验分析研究不同介质循环速度对木材干燥速度的影响.结果表明,介质循环速度对干燥速度的影响显著,但其影响随木材含水率（MC）的降低而减弱.在低介质循环速度条件下,试件MC大于45％时,表现为木材干燥速度和木材含水率偏差（△MC）随循环风速的增加而增加,呈显著正相关关系;试件MC介于35％ ～ 45％之间时,正相关关系存在但不显著;试件MC小于35％时,干燥室内循环风速的大小不影响木材的干燥速度和木材含水率偏差（△MC）.对试件表层含水率分析,试件表层含水率大于25％时,试件表面循环风速对试件表层含水率的影响显著;试件表层含水率小于25％时,试件表面循环风速对试件表层含水率的影响很小,不同循环风速下试件表层含水率基本一样.     

液相色谱串级质谱同时测定木制品中3种有机磷酸酯阻燃剂

为建立有效的阻燃剂的使用规范和为监管制度提供理论依据,本文建立了微波辅助萃取,液相色谱串级质谱法同时测定木制品中3种有机磷阻燃剂分析方法,并考察了萃取溶剂、萃取条件、流动相对试验结果的影响。结果表明,以丙酮为萃取溶剂,70℃微波辅助萃取30 min,利用多反应检测MRM模式,TCEP、TDCP在线性范围0.02～1.0 mg/kg,TCPP在线性范围0.002～0.2 mg/kg内质量浓度与响应值呈现良好的线性关系,定量下限分别为27、50、8μg/kg,加标回收率82.7%～98.3%,相对标准偏差1.8%～10.8%。该方法操作简单,提取效果较好,能够有效的检测木制品中三种有机磷酸酯阻燃剂。     

Yield of greenhouse-grown tomato in substrates containing coir and parboiled rice or burnt rice hulls

Substrate components produced in the sub-tropics or tropics were combined in various proportions as substrates for the greenhouse production of ‘Big Beef’ tomato. Coir was mixed with parboiled rice hulls (PBH) or burnt rice hulls (BRH) at 0, 25, 50, 75, or 100% volume. Fruit fresh weights at equal proportions of BRH or PBH in coir were similar, with the greatest fruit yields achieved with 50 to 100% coir (0 to 50% PBH or BRH). Compared to 100% coir, PBH in coir decreased substrate container capacity and increased air porosity, while BRH in coir increased container capacity and decreased the air porosity. Pre-plant fertilisation of the PBH + coir substrates (superphosphate, gypsum, trace elements, calcium nitrate, and surfactant) increased fruit yield significantly. Substrates containing 50 to 100% coir with BRH or PBH yielded greater fruit fresh weights than was achieved in in 70% BRH + 30% gravel (a typical substrate used in the Dominican Republic), and reusing the 70% BRH + 30% gravel led to a 36% increase in fruit fresh weight. Fruit fresh weights in 100% coir or 75% coir plus 25% PBH or BRH were similar to those achieved in a commercial peat-lite. Herein we report on substrates made from tropical components that perform similarly to a peat-based substrate in the production of greenhouse-grown tomatoes.     

Disulphide structure of high-molecular-weight (HMW-) gliadins as affected by terminators

This study aimed at elucidating SS-bonds of HMW-gliadins (HGL) from wheat with the focus on terminators of glutenin polymerisation. HGL from wheat flour extracts non-treated or treated with the S-alkylation reagent N-ethylmaleinimide (NEMI) were compared. HGL from wheat flour Akteur were isolated, hydrolysed with thermolysin and the resulting peptides pre-separated by gel permeation chromatography and analysed by liquid chromatography/mass-spectrometry using alternating electron transfer dissociation/collision-induced dissociation. Altogether, 22 and 28 SS-peptides from samples without and with NEMI treatment, respectively, were identified. Twenty-six peptides included standard SS-bonds of α- and γ-gliadins, high-molecular-weight and low-molecular-weight glutenin subunits. Eleven SS-bonds were identified for the first time. Fifteen peptides unique to HGL contained cysteine residues from gliadins with an odd number of cysteines (ω5-, α- and γ-gliadins). Thus, gliadins with an odd number of cysteines, glutathione and cysteine had acted as terminators of glutenin polymerisation. Decisive differences between samples without and with NEMI treatment were not obvious showing that the termination of polymerisation was already completed in the flour. The two HGL samples, however, were different in the majority of ten peptides that included disulphide-linked low-molecular-weight (LMW) thiols such as glutathione and cysteine with the former being enriched in the non-treated HGL-sample.     

育苗轻型基质块配方研究

为充分利用南方果树废弃物资源,以香蕉菠萝废弃茎叶堆肥和椰糠作为基质材料,添加粘合剂、固化剂、改良剂,制作出基质块。采用正交法设定基质块配方,通过测试分析基质块的理化性状,确定最佳的基质块配方。结果表明,香蕉菠萝废弃茎叶堆肥和椰糠的配比是影响基质块理化性状的主要因素,各因素影响的主次顺序为:基质配比改良剂粘合剂固化剂;综合分析,A3B2C3D3组合配方具有最佳的理化性状,即基质配比(堆肥:椰糠)为4:6,粘合剂(聚乙烯醇)为4%,固化剂(硼砂)为2.5%,改良剂为140%。     

淮北地区氮肥群体最高生产力水稻钾素吸收利用特征

以淮北地区有代表性的34个中熟中粳品种为试材,设置7个氮肥水平(0、150.0、187.5、225.0、262.5、300.0、337.5 kg hm~(–2)),得出各品种的最高产量,将该最高产量定义为氮肥群体最高生产力。在此基础上,明确处于顶层水平(≥10.50 t hm~(–2))、高层水平(9.75~10.50 t hm~(–2))、中层水平(9.00~9.75 t hm~(–2))和底层水平(≤9.00 t hm~(–2))水稻品种的钾素积累、分配及转运特征。结果表明,4个生产力等级水稻品种地上部植株、茎鞘和叶片的含钾率在拔节期最高;抽穗期顶层水平品种的这3个参数高于其他3个等级的品种;穗部含钾率差异不显著。随着氮肥群体生产力等级的提高,钾素总积累量增多;拔节前底层水平钾素积累量最多,两年平均为120.56 kg hm~(–2),比例占50.56%,顶层水平为最少,两年平均为108.02 kg hm~(–2),比例占35.99%;拔节至抽穗期和抽穗至成熟期顶层水平钾素阶段积累量及比例显著高于其他3个等级。移栽至拔节期,钾素积累速率为中层底层高层顶层水平,拔节后则为顶层高层中层底层水平。叶片的钾素转运量及转运率明显高于茎鞘;顶层水平叶片的钾素转运量高于其他3个等级,高层水平叶片的转运率最高;穗部增加量随生产力等级的递增而变大;抽穗到成熟期,茎鞘、叶片对穗的钾素转运贡献率表现为底层最高,中层次之,顶层最低。4个等级水稻品种籽粒生产率和百千克籽粒吸钾量差异不显著;钾素偏生产力和钾收获指数均表现为顶层高层中层底层水平。总之,氮肥群体最高生产力越高,水稻中后期植株钾素积累量及器官对钾素的吸收利用效率越显著。抽穗后保持较高的钾素吸收利用及转运效率是高产水稻品种的重要特征。     

不同培养方法及培养密度对绵羊腔前卵泡发育的影响

通过对绵羊腔前卵泡培养方法的研究,能够探索出适宜绵羊腔前卵泡生长发育的培养条件,以及为进一步揭示绵羊卵泡生长发育的规律奠定一些基础。试验一通过使用微滴法和琼脂培养基法培养腔前卵泡,观察其对绵羊腔前卵泡生长的影响;试验二通过绵羊腔前卵泡单独培养与群体培养,探讨不同培养密度对绵羊腔前卵泡生长的影响。试验结果显示,使用微滴法与琼脂培养基法培养的绵羊腔前卵泡,在培养3天时,卵泡直径增加值和存活率差异均不显著(P0.05);但培养6天时,琼脂培养基法培养的腔前卵泡的直径增加值和存活率均极显著高于微滴法培养的腔前卵泡(P0.01);在使用琼脂培养基培养的条件下,对绵羊腔前卵泡进行单独培养和群体培养,在培养的6天时间内二者卵泡直径增加值和存活率差异均不显著(P0.05)。试验结果表明,琼脂培养基法是较为适宜的绵羊腔前卵泡体外培养方法;培养密度对绵羊腔前卵泡体外培养并无显著影响。     

基于nanoUPLC-MS/MS的螺旋藻游离肽组成分析

为了研究螺旋藻中的多肽成分,以钝顶螺旋藻为原料,采用超滤法提取螺旋藻中的游离肽,利用nanoUPLC-MS/MS和PEAKS Studio分析谱图信息,结合NCBI数据库进行比对和从头测序分析,获得游离肽的结构组成和百分含量信息。结果表明,利用数据库比对法和从头测序法,分别得到可信的游离肽4 485个和20 597个,匹配到的蛋白质有1 036种。数据库比对结果中的游离肽主要为七肽到二十一肽,少量为二十一肽以上;从头测序结果中游离肽主要为二肽到十六肽,少量为十六肽以上。数据库比对结果中百分含量最高的游离肽是十肽,为15.95%;从头测序结果中百分含量最高的是五肽,达到24.09%。本研究结果为螺旋藻蛋白资源的进一步开发和利用提供了依据。     

超高效液相色谱-串联质谱法测定牛奶和奶粉中五种苯并咪唑类药物

为建立牛奶及奶粉中5种苯并咪唑类药物(阿苯达唑、芬苯达唑、奥芬达唑、噻苯达唑、苯硫氨酯)简便、准确的分析检测方法,以固相萃取为净化手段,采用Acquity UPLC^® BEH C₁₈(100 mm×2.1 mm,1.7 μm)色谱柱进行分离,电喷雾离子源(ESI⁺),多反应监测(MRM)模式检测。结果表明,5种苯并咪唑类药物在1~500 μg·L^-1范围内呈线性相关,相关系数(r)均大于0.996,加标平均回收率介于91.7%~97.8%之间,相对标准偏差(RSD)在1.4%~6.5%之间,基质效应均小于15%。5种药物的检出限均在0.1~3 μg·kg^-1范围内,定量限均在0.5~10 μg·kg^-1范围内。该方法操作简单、快速且灵敏度高,重现性好,能够用于牛奶及奶粉5种苯并咪唑类药物的同时测定。