Responses of Lotus corniculatus to environmental change. 2. Effect of elevated CO2, temperature and drought on tissue digestion in relation to condensed tannin and carbohydrate accumulation

Clonal plants of three genotypes of Lotus corniculatus (cv Leo) were grown in eight controlled environments under combinations of two temperature regimes, two CO₂ concentrations and two watering regimes. Condensed tannins (proanthocyanidins), in-vitro digestibility, initial rates of gas evolution (as an indicator of the initial rates of fermentation of the substrate), volatile fatty acid evolution, and non-structural carbohydrate (NSC) levels were determined in leaves, stems and roots at full flowering. Under control conditions (average midsummer conditions in the United Kingdom) the total condensed tannin content of leaves varied six-fold between genotypes but condensed tannin contents in stems and roots were similar. Condensed tannin levels were significantly increased in leaves and stems of all three genotypes by doubling the CO₂ concentration while raising the temperature towards the optimum for growth significantly reduced condensed tannin levels. Drought stress significantly reduced condensed tannin levels in leaves and, particularly, in roots. Nutritive value was inversely related to condensed tannin levels in leaves and a negative relationship was observed between condensed tannin concentrations of more than 25–30 g kg⁻¹ dry matter and the initial rates of gas evolution when subjected to in-vitro fermentation with rumen micro-organisms. In leaves, digestibility was significantly increased by drought and by increasing temperature but reduced by high CO₂. In stems, digestibility was significantly increased by drought, but not significantly affected by increasing temperature, or by high CO₂ alone. In roots, digestibility was significantly increased by drought, and decreased by increasing temperature or CO₂. Increasing the growth temperature towards optimum growth reduced the content of NSC in all tissues with the greatest changes occurring in root tissue. Doubling the CO₂ concentration increased NSC levels in leaves and stems with starch content more than doubled under high CO₂ while, in roots, increased levels were only observed in combination with drought stress. There was a linear correlation between condensed tannin concentration and total NSC that was positive for leaves, neutral for stems and negative for roots. The relationship between carbohydrate levels and rates of gas production was negative for leaves and positive for stem and roots. © 1999 Society of Chemical Industry     

不同干燥方式对藕片品质的影响

目的 探究不同干燥方式对藕片品质的影响。方法 测定不同热风干燥温度下不同厚度藕片的干燥曲线,并表征其水分迁移特征,以真空冷冻干燥为对照,比较不同干制条件下藕片理化特性(外观、褐变度、色泽、收缩率)和营养品质[维生素C(vitamin C, VC)、总黄酮、总酚含量]的差异。结果 热风干燥过程中,藕片干燥速率随温度升高、厚度减小而增大,其中,干燥温度为50℃时,藕片无法干燥至安全水分范围(干基含水量≤15%), 60℃、70℃温度下,不同厚度藕片最终含水量均可降至安全水分范围;水分迁移特征显示藕片干制过程中干燥前期游离水蒸发,固定水和束缚水比例增加,最终干制藕片中水分主要以束缚水形式存在;不同热风干燥条件对比之下,温度为60℃、厚度10mm、保留水分15%时,干制藕片色泽较好、褐变和收缩率最低,总黄酮含量、总酚含量及VC保留量较高,营养保留程度与真空冷冻处理得到的藕片营养品质接近,干制效果优于其他干燥条件。结论 从藕片理化性质、营养品质及干燥效率等相关方面考虑,热风干燥温度为60℃,切片厚度为10 mm,保留水分15%左右,干燥时长大约在280 min左右时,藕片理化特性和营养品质得到最...     

荷叶中黄酮提取工艺的研究

本研究采用乙醇提取荷叶中的黄酮成分.对固液比、浸提温度、浸提时间和乙醇浓度进行了单因素梯度实验,确定了其条件范围;通过进一步正交实验得到荷叶黄酮提取的最佳因素组合.醇提荷叶黄酮的最佳因素组合:乙醇浓度65%,浸提温度35℃,浸提时间2.5h,固液比1:25.     

电厂办公自动化系统

根据电厂办公自动化系统要求高效、快捷和用户远程交互的特点,设计了基于LotusNotes平台,具有公文、办公、个人事物和信息服务等管理功能的电厂办公自动化系统,该系统实现了电厂内部办公信息的收集、处理、流动和共享,以及与外部用户的连接。并已在多个电厂成功地使用,具有推广应用潜力。     

漪碧涵虚天人合一--保定古莲花池创作意象解读

融园林、书院、行宫三位一体的古莲花池历经沧桑,形象地反映了这一时期宫苑园林的时代特征。莲池寄情山水、崇尚自然,龟藏了中国传统园林文化的体系。通过对莲池意匠的分析,解读其在工程技术、艺术形象等方面的创作思想,解剖其隐藏在形式语言背后的文化思想及审美意境。     

冬荷品种选育与栽培技术研究--以三水荷花世界为基地

冬荷在亚热带地区四季常绿,花期长达10个月(3月～12月),性耐寒,5℃时叶不枯黄,10℃左右花蕾出水,18℃～20℃开花.花繁密,结实率高,地下茎不会膨大成藕,所以比普通荷花观赏价值高.广东三水荷花世界用3年时间,采用以藕鞭为材料的配套栽繁技术,选育出3个冬荷新品种,可在我国南方沿海地区和东南亚各国推广应用.     

Lotus Domino/Notes在超高压局公文管理中的应用

系统采用目前极为流行的群件系统——LDtus Domino／Notes，完成了哈尔滨超高压局在公文流转过程中的各种计划表、申请表、规程、报表、发文、收文的网上起草、审批、下发等，使得各种公文的管理、流转实现了办公自动化，实现了东北公司对办公自动化系统的整体规划。从总体设计、具体实现、技术问题、安全机制、系统特点等方面对系统进行了介绍与探讨。     

基于Lotus Notes的高校办公自动化系统设计与实现

讨论了Lotus Notes做为办公自动化的平台的优势和特点。并系统介绍了西安邮电学院办公自动化的系统设计与实现。     

基于Lotus Domino／Notes的企业办公自动化系统开发研究

本文根据企业信息处理和日常办公的特点,提出将日常办公和企业信息管理系统集成的观点;分析了Lotus Domino／Notes的特性,介绍了基于Lotus Domino／Notes的企业办公自动化系统的开发研究方案。     

Fabrication of highly transparent and superhydrophobic silica-based surface by TEOS/PPG hybrid with adjustment of the pH value

Preparation of superhydrophobic silica-based thin film with high transmittance (T%) in the visible light region by adjusting different pH value of mixing solution has been developed. The hybrid films were coated by the mixing solution which included precursor solution (sol–gel process) and polypropylene glycol (PPG) polymer solution. Rough surfaces were obtained by removing the organic polymer at high temperature and then the hydrophobic groups bonded onto the films were obtained by the reaction with hexamethyldisilazane (HMDS). Characteristic properties of the as-prepared surface of the films were analyzed by contact angle measurement, scanning electron microscopy (SEM), atom force microscopy (AFM), UV–VIS scanning spectrophotometer and Fourier transform infrared (FT-IR) spectrophotometer. The experimental parameters were mainly varied by the pH value (0, 1, 2.3, 6 and 8) of the mixing solution. The result showed that the contact angle of the film was greater than 150° and the transmittance of the film was greater than 90% simultaneously when the pH value of mixing solution was adjusted to 1. In addition, the highly transparent superhydrophobic surfaces was obtained by adding 20 μL acid solution into the mixing solution, which the contact angle of the film was 156.3° as well as the transmittance of the film at the 600 nm visible light was 97.9%.