Sulfonated tea waste: A low-cost adsorbent for purification of biodiesel

In the present work, the crude biodiesel produced from spent fish frying oil through alkaline catalyzed transesterification was purified using a low-cost adsorbent viz. sulfonated tea waste. After separating the glycerol, the crude biodiesel was purified using the suggested adsorbent. Various methods of purification using the said adsorbent were applied such as purification using adsorption column chromatography and shaking methods. The results showed that purification using adsorption column chromatography exhibited the bst result. Properties of the purified fuels were determined and found conformed to those specified by the ASTM standards. For the sake of comparison, purification using zeolite and water washing method was also investigated. The result indicated that the suggested adsorbent was more successful on purification of the crude biodiesel compared to other methods.     

黑木耳和茶叶黄酮复配物的抗氧化活性

研究了黑木耳和茶叶黄酮复合对两种自由基体系的活性清除。结果表明,黑木耳和茶叶黄酮复合对羟基自由基（OH.）和超氧阴离子自由基（O2-.）均有较强的清除作用,且随着用量的增加清除效果增强。在同样用量的情况下,其清除作用明显强于单种黄酮的抗氧化作用,初步说明两种黄酮的复合可增强清除自由基的活性。     

茶园土壤速效磷乡镇尺度下空间异质性对比分析——以江浙地区优质名茶种植区为例

土壤中磷素的含量对土壤肥力和茶叶品质起着至关重要的作用,探讨土壤磷素含量的空间分布特征及其影响因素,可以为茶园管理和茶叶品质的提升提供理论指导。以江苏省东山镇和浙江省溪龙乡两个优质名茶种植区为例,在遥感影像和DEM数据的基础上,应用地统计学方法,对比研究了两个茶园土壤速效磷含量的空间异质性特征。结果表明:(1)按土壤肥力等级标准,东山镇和溪龙乡速效磷含量的平均水平均较高,利于茶叶生长;(2)东山镇和溪龙乡速效磷含量的变异系数分别为0.46和0.52,均属于中等强度变异;(3)空间插值结果显示,东山镇和溪龙乡速效磷在空间上都具有相连成片的特征,但东山镇速效磷呈阶梯状分布特征,而溪龙乡速效磷则呈辐射状分布特征;(4)东山镇和溪龙乡速效磷的块基比值分别为0.343和0.142,表明溪龙乡速效磷受随机性因素的影响较东山镇的小,而受结构性因素的影响较东山镇的大。     

晋江西溪流域茶园降雨径流产污特征

在野外模拟降雨条件下,开展了晋江西溪流域茶园和裸地的径流产沙及氮磷养分流失过程对比实验,研究结果表明,在相同降雨强度下,3种下垫面径流和产沙量顺序均为:裸地＞2年茶园＞4年茶园,径流量与产沙量之间呈显著正相关.对地表径流水相而言,2年茶园、4年茶园和裸地的TN流失量分别为:461.29、129.38和107.86 mg/m2;NO3-N流失量分别为:286.42、98.58和103.00 mg/m2,均占TN流失量的60％以上;NH4-N流失量分别为:48.67、16.19和4.42 mg/m2;Tp流失量分别为:34.71、16.47和23.88 mg/m2.对径流泥沙相而言,2年茶园、4年茶园和裸地的TN流失量分别为:379.28、44.81和747.16 mg/m2,占流失总量的比重在25.72％～87.93％之间;TP流失量分别为:27.94、4.17和58.85 mg/m2,占流失总量的比重在53.42％ ～68.36％之间.茶园的N、P主要随径流流失,而裸地以泥沙迁移为主.这说明茶叶种植具有一定的水土保持效应,且种植年限较长的茶园可显著减少随径流泥沙进入水体中的N、P元素.     

How Competing Securitized Discourses over Land Appropriation Are Constructed: The Promotion of Solar Energy in the Israeli Desert

Although solar farms are often favorably received by the public due to their contribution to clean energy, they are not conflict-free. In various contexts, this land-intensive technology often competes with other land uses like agriculture, nature reserves, and army training. As a result of this competition, interest groups often seek political leverage in order to prioritize their spatial use. Framing their uses as existential is one possible way to capture the attention of decision-makers. Yet, this securitization process may create a framing contest whereby different actors use similar securitization language to promote different land uses. This study is the first attempt to trace how this framing contest of securitized discourses over land appropriation is constructed. It is based on the Israeli experience of promoting solar energy in the Negev Desert, an area conceived as available to solar development. Through an analysis of protocols of Israeli policy-makers’ meetings between 2002 and 2011, the study documents the ways in which players adopt securitized language concerning various land uses such as energy, food, ecology, and traditional (national) security. The study found that the use of securitized framing varies between uses, forums, actors, and sectors. Yet competition between securities discourses remained uneven as, in the Israeli context, many players find it difficult to challenge the hegemonic role of traditional (national) security.     

茶树中镉、砷元素的吸收累积特性

通过田间调查及盆栽试验,探讨砷、镉元素在茶树中的分布规律及吸收累积特性。结果表明,砷、镉元素在茶树体内活性较低,大部分被吸收根固定,向地上部运输的比例较低。正常状况下,砷、镉元素在茶树体内由高到低的分布次序是:吸收根>茎(生产枝)或主根>老叶(当年生成熟叶)>新梢(1芽2叶)。茶树受砷、镉污染时,吸收根对阻止土壤砷、镉向新梢转移起到明显的缓冲及屏障作用。当镉添加量为6 mg.kg-1时,茶树的叶绿素含量开始受到显著的负面影响,但光合速率、蒸腾速率及气孔导度变化不明显;当镉添加量为20 mg.kg-1时,上述4项指标均显著降低。砷添加量为50 mg.kg-1时,对茶树光合速率、蒸腾速率及气孔导度产生显著负面影响,但对叶绿素含量的影响不明显;砷添加量为200 mg.kg-1时,则对光合速率、蒸腾速率及气孔导度无显著影响。     

间种高粱及施用大颗粒尿素对茶园N2O排放的影响

茶园施肥量大、氧化亚氮(N_2O)排放系数高,且近年来我国茶园面积不断扩大,使茶园成为重要的农业N_2O排放源,亟需有效的茶园N_2O减排措施.本研究在我国中亚热带典型丘陵茶园,通过设置间种高粱、施用大颗粒尿素和常规施肥3种管理措施,观测不同管理措施下茶园土壤N_2O及相关环境因子动态,旨在解析茶园土壤N_2O排放的主控因子和明确提出的减排措施的有效性. 2 a的田间试验结果表明:①茶园土壤N_2O排放通量与土壤化学性质、温度及降雨有显著的相关性,土壤物理性质和土壤化学性质的交互作用对N_2O排放影响最大,土壤化学性质中的NO~-_3-N含量是决定N_2O排放量大小的最主要因素,茶园土壤N_2O减排研究的工作重点在于如何减小土壤中的NO~-_3-N含量;②间种高粱在未影响茶叶产量的前提下减少了51.2%的N_2O排放,从缓解全球气候变暖角度看,间种高粱是本研究中最佳的茶园管理措施;③施用大颗粒尿素在提高29.5%的茶叶产量同时减少了34.7%的N_2O排放,从兼顾经济效益及缓解全球气候变暖的角度看,茶园中施用大颗粒尿素则是本研究中最佳的施肥措施.     

EGSB-CAAS工艺处理茶多酚废水的工业化研究

应用“EGSB－CAAS”工艺处理茶多酚废水的工业化研究表明，当进水COD为36960－43182mg/L、SS为6562－10904mg/L时，经混凝气浮预处理后，采用“EGSB－CAAS”工艺进行处理，系统COD和SS去除率达99％以上，出水可达标排放。     

氮肥深施及间种白三叶草对茶园N2O排放的影响

近年来我国茶园面积不断扩大,茶园施氮(N)量大、N_2O排放量高,是重要的N_2O排放源,开展茶园的N_2O减排研究十分有必要.本研究在位于我国亚热带丘陵区的典型茶园,通过设置常规施肥、氮肥深施和间种白三叶草这3种处理,观测不同施肥及管理措施下茶园土壤N_2O排放及其相关土壤环境因子动态,旨在明确不同措施对茶园N_2O排放的减排效果,并解析相关影响因子.通过3 a的田间试验表明,亚热带丘陵茶园具有较高的N_2O排放,N_2O-N年累积排放量高达5. 1～10. 1 kg·hm-2.N_2O排放主要发生在春夏季,当土壤温度低于15℃,其排放主要与土壤温度呈正相关;当温度高于15℃,则主要与土壤含水量、土壤NH4+-N和NO3--N含量呈正相关.三年间茶园间种白三叶草较常规施肥未显著影响N_2O排放,肥料深施在降雨量较高年份增加了茶园N_2O排放,间种白三叶草和肥料深施未显著影响茶叶产量.本研究表明,亚热带茶园间种白三叶草减排N_2O的效果不显著,不减少氮肥用量下氮肥深施未能降低N_2O排放,今后有必要研究肥料深施配合氮肥减量来减排N_2O.     

茶园土壤和茶叶中重金属的监测与污染评价

测定了西南地区主要茶园土壤和茶叶中的重金属Pb,Cr,Cu,Cd,Hg和As含量,结合茶园土壤和茶叶的卫生质量标准,采用单因子污染指数法和Nemerow污染指数法进行污染评价。结果表明:西南地区茶叶和茶园土壤中6种重金属的含量都在相应的质量标准范围内,单因子污染指数和Nemerow污染指数均<1.0。但乐山和川茶群体土壤中的Cd综合污染指数达到0.69,接近安全等级的上限0.70。总体看来茶叶和茶园土壤未受这6种重金属元素的污染,茶叶和茶园土壤环境质量总体良好。缙云山茶和银芽中Cd和Hg是高富集元素,川茶群体中Hg是高富集元素。