不同潮水量条件下普洱茶渥堆过程化学成分的变化

通过设置不同潮水量进行实验室模拟普洱茶渥堆过程,系统地研究堆表与堆芯主要理化成分含量的变化规律,找出普洱茶快速模拟发酵的潮水量。结果表明:至渥堆结束,茶坯的茶多酚、儿茶素、茶黄素、茶红素、氨基酸的含量均呈减少趋势,水溶性糖、茶褐素、咖啡碱的含量则呈增加趋势。不同潮水量条件下渥堆茶样的堆温以及参与发酵的微生物的差异,显著地影响普洱茶的品质。结合感官评价得出,潮水量为45%的普洱茶表现出较佳的品质。

不同潮水量下普洱茶渥堆过程中微生物及酶活变化研究

运用实验室规模模拟渥堆,研究不同潮水量(30%、35%、40%、45%)下普洱茶渥堆过程中微生物及酶活的变化。结果表明:渥堆过程中,初期霉菌大量生长,呈现优势菌种,后期堆温下降,酵母、细菌开始大量生长。35%潮水量下多酚氧化酶活性显著高于其它组,且堆温对多酚氧化酶活性影响不大,渥堆过程中微生物不分泌过氧化物酶。45%潮水量下蛋白酶活后期低于原料样,相比其他组显著偏低,说明潮水量过高、堆温降低会在一定程度上抑制蛋白酶酶活。淀粉酶酶活随潮水量增加显著增强,但潮水量40%与45%差异不明显。40%、45%潮水组茶胚果胶酶、纤维素酶酶活高于30%、35%。因此,选择合适的潮水量有利于普洱茶品质与功能的提高。

潮水量对木地板渥堆发酵茶品质影响研究

探索不同潮水量的相同等级毛茶原料木地板渥堆过程中含水率、堆温变化及其对熟茶感官品质的影响,结果表明,在相同的室温条件下渥堆34 d,潮水量45%的茶堆在渥堆结束阶段含水率、堆温偏高,容易造成熟茶的发酵程度偏重;潮水量40%的茶堆生产的熟茶其品质更接近传统熟茶;潮水量35%的茶堆生产的熟茶理化指标、生产收率较高,以其作为原料生产的熟茶具有成为深加工产品原料的潜质。

普洱茶发酵过程中潮水用量对茶品质的影响

普洱茶(熟茶)是指云南大叶种晒青散茶或普洱茶(生茶)在特定的环境条件下,经微生物、酶和湿热等综合氧化作用,其内含物质发生一系列转化,而形成普洱茶(熟茶)独有品质特征的过程。在普洱茶的渥堆"发酵"过程中,由于不同潮水量的茶坯所着生的微生物及堆温、含水率的差异,导致不同潮水量的茶坯中茶多酚、茶黄素、可溶性糖、氨基酸等特征性成分变化快慢不一。

水文站流量计算及定线检验系统设计和应用探讨

水文资料整编中，为了保证流量关系线的正确合理，需要进行符号检验、适线检验和偏离数值检验（简称3项检验）。而要进行流量定线检验，必须保证原始流量资料的准确。现实中由于价格和使用条件局限，声学多普勒剖面流速仪（ADCP）在水文站使用还不是很普及，相当数量水文站流量计算和定线检验还需依赖人工计算，既不可靠，又严重制约了广大基层水文工作者创造性的发挥。基于面向对象思想，使用VISUAL C＋＋语言自主设计开发了水文站流量计算及定线检验系统，能够进行河道流量计算、一潮水量计算和流量定线的3项检验，实践中取得了较好的效果。

水文站流量计算及定线检验系统设计和应用探讨

随着社会经济的不断发展,水文站流量计算及定线检验系统设计和应用已经逐渐得到人们的广泛关注,且取得了一定的研究成果。现阶段,随着现代化信息技术手段信息竞争环境错综复杂和日益增多,以至于不能依赖管理者自身的智慧来确保水文站管理的有效以及决策的成功与否。因此,有必要参照团队精神和集体智慧,才能在信息竞争中立于不败之林。简要叙述了水文站流量计算及定线检验系统,并深入研究了水文站的系统设计,目的是更好的开展具体的水文站工作。

上海地表水资源估算方法和特点

水是人类生存和社会发展的必要条件之一。实践证明,不仅农业生产需要水,工业和城市建设都离不开水。 上海是我国最大的工业城市,工农业总产值约占全国的1/7。30多年来,特别是从五十年代后期开始,上海城市人口增加很快,工农业生产有了较大发展,近郊兴建了一批新工业区,开辟了12个卫星城镇,已经由一个单一城市发展为群体组合的大城市,成为我国最大的综合性工业基地。随之而来,一方面全市用水量增长很快。

Analysis and Prediction of Influence Imposed on Jiaozhou Bay Tidal Currents and Tidal Energy of M_2 Tidal System by Jiaozhou Bay Reclamation

The 3-D ECOMSED ocean model was applied to establish a time-dependent boundary model for Jiaozhou Bay (JZB), in which the operator-splitting technique was used and the ‘dry and wet’ method was introduced. The influence caused by JZB reclamation on the surface level, residual currents, tidal system and tidal energy of M2 tidal system were predicted and analyzed. The results show that JZB reclamation has slight impact on the M2 tidal system, in which the variation of amplitude and phase is less than 1%.The changes of the currents and residual currents in Qian Bay and near the reclamation areas are greater, but in other areas the changes are smaller, in which the currents have a change of around 1%, while the residual currents change ranges from 1.82%–9.61%. After reclamation, the tidal energy fluxes increase by 2.62%–5.24% inside and outside the JZB mouth, but decrease by 20.21%–87.23% near Qian Bay and the reclamation area.

Rice Yield and Yield Components as Influenced by Phosphorus and Nitrogen Application Rates in the Moist Savanna of West Africa

A two-year field experiment was conducted to evaluate the influence of nitrogen （0, 30, 60, and 120 kg N ha^-1） and phosphorus （0, 30, and 60 kg P2O5 ha^-1） application on grain yield and yield components of five New Rice for Africa （NERICA） cultivars, their parents, and a check on a degraded soil in the moist savanna of Nigeria. Nerica 14 recorded the highest grain yield of 1.3 mg halcompared to the other NERICA cultivars. It also produced significantly （P 〈 0.05） longer panicles （19.24 cm）, higher sink capacity as determined by thousand-kernel weight （30.3 g）, and a higher potential for partitioning photosynthates （45.15%） into grains than the other cultivars. N × P interaction effect on grain yield was significant （P 〈 0.05） with moderate P （60 kg P2O5 ha^1） and moderate N （60 kg N ha^-1） resulting in optimum grain yield （1.7 mg ha^-1）. Thus, moderate N and P were recommended for the production of NERICA varieties in low-input smallholder upland rice production systems of the moist savanna of Nigeria.

Responses of soil moisture to vegetation restoration type and slope length on the loess hillslope

Soil moisture, a critical variable in the hydrologic cycle, is highly influenced by vegetation restoration type. However, the relationship between spatial variation of soil moisture, vegetation restoration type and slope length is controversial. Therefore, soil moisture across soil layers（0-400 cm depth） was measured before and after the rainy season in severe drought（2015） and normal hydrological year（2016） in three vegetation restoration areas（artificial forestland, natural forestland and grassland）, on the hillslopes of the Caijiachuan Catchment in the Loess area, China. The results showed that artificial forestland had the lowest soil moisture and most severe water deficit in 100-200 cm soil layers. Water depletion was higher in artificial and natural forestlands than in natural grassland. Moreover, soil moisture in the shallow soil layers（0-100 cm） under the three vegetation restoration types did not significantly vary with slope length, but a significant increase with slope length was observed in deep soil layers（below 100 cm）. In2015, a severe drought hydrological year, higher water depletion was observed at lower slope positions under three vegetation restoration types due to higher transpiration and evapotranspiration and unlikely recharge from upslope runoff. However, in 2016, a normal hydrological year, there was lower water depletion, even infiltration recharge at lower slope positions, indicating receiving a large amount of water from upslope. Vegetation restoration type, precipitation, slope length and soil depth during a rainy season, in descending order of influence, had significant effects on soil moisture. Generally, natural grassland is more beneficial for vegetation restoration than natural and artificial forestlands, and the results can provide useful information for understanding hydrological processes and improving vegetation restoration practices on the Loess Plateau

钱塘潮涌杭州湾

杭州湾的沧海桑田 在我国风景名胜杭州市的东部,有一个令人瞩目的海湾,这就是钱塘江的入海口--杭州湾,它的形状很像一只口朝东的大喇叭.在每年农历8月,有大批的游客前往那里观看世界闻名的钱塘潮.千百年来,海潮与杭州湾相生相克,让杭州湾发生着令人眼花缭乱的变化.