Improvement in synthesis method of 4-hydroxycoumarin

考察以邻羟基苯乙酮与碳酸二乙酯为原料反应合成4-羟基香豆素的新方法。通过正交实验对相转移催化剂添加量、碱性缩合剂用量、加料温度、反应时间进行考察,得出此方法合成4-羟基香豆素的较优工艺条件为:原料摩尔比为n(邻羟基苯乙酮):n(碳酸二乙酯):n(甲醇钠):n(聚乙二醇-400)=1:2:3.0:0.42,在5~10℃温度下加料,120℃反应2.5 H,收率为65.7%。产物经熔点、Ir、--1HnMr、--(13)CnMr进行鉴定。4-Hydroxycoumarin was synthesized by the reaction of 2-hydroxyacetophenone with diethyl carbonate via the catalyst of sodium methoxide and polyethylene glycol-400.According to the orthogonal design experiments about the dosages of polyethylene glycol-400,the dosages of alkali,the feed temperture and the reaction time.The optimal reaction conditions were as follows:xylene as the solvent,n(2-hydroxyacetophenone):n(diethyl carbonate):n(sodium methoxide):n(polyethylene glycol-400) = 1:2.0:3.0:0.42.Feed under the temperature of 5—10℃.The reaction mixture was heated at 120℃for 2.5 h.4-Hydroxycoumarin was produced in 65.7%yield.The product was characterized by Melting point meter,IR,--1HNMR and --(13)CNMR

东北三省畜禽养殖时空分布特征及粪便养分环境影响研究

东北三省是我国重要的粮食生产和工业基地。近年来,随着经济的发展和产业结构的调整,畜禽养殖业发展迅速,同时畜禽粪便的产生量也将快速增加。畜禽粪便作为农田肥料有其不可替代的优势,但是如果超过耕地的承载量将会对环境造成潜在的影响和压力。本文主要通过对东北三省畜禽养殖数量、养殖结构及空间布局的时空分析,采用养分平衡法研究和评价该地区畜禽粪便中氮、磷养分对环境的影响和污染风险。研究结果表明,东北三省吉林中部一直延伸到辽宁东南部地区畜禽养殖密集,耕地养分的大量盈余可能对环境构成污染威胁。黑龙江省畜禽养殖对环境的影响小,还有一定的发展空间

Imaging by a joint tomography of direct wave traveltime and reflection wave traveltime in crosswell seismic and its application

本文利用直达波的旅行时与反射波的旅行时联合反演两井之间的速度分布,在计算方法中加入声波测井获得边界上的先验信息,如慢度分布和反射层位置,可提高计算时的收敛性能与计算效率。在层析反演过程中,采用阻尼lSQr算法求解,在求解的过程中施加一定的阻尼,能有效地抑制数据误差较大时的影响,提高反演的抗噪声能力。应用正演模型验证了方法的可行性。实际资料处理表明,该方法的层析速度纵、横向分辨率较高,在井旁与声波速度吻合较好,计算精度较高。The paper discusses a joint tomography of direct wave traveltime and reflection wave traveltime in crosswell seismic.Using direct wave traveltime and reflection wave traveltime between wells with well information such as slowness distributions and reflection interface positions,this tomography method benefits a good astringency.The damp LSQR arithmetic is applied in the tomography procedure.It can effectively improve de-noise ability.Its application to the forward modeling proves its feasibility.Applications to field datasets indicate that high resolutions are obtained for both vertical and horizontal direction;and good velocity matching around the wells.国家“863”计划“油藏综合地球物理技术”课题(No.2007AA060500)资

畜禽养殖过程中雌激素的排放及其环境行为

由于存在广泛和较强的内分泌干扰性,环境雌激素越来越受到关注,其中人与动物排放的天然类固醇雌激素(雌酮、雌二醇和雌三醇)具有最强的干扰性。综述了畜禽养殖过程中天然雌激素的排放、危害以及其物化性质,并结合国内外近期研究阐明了天然雌激素的吸附、降解和迁移转化等环境行为。在目前雌激素研究现状的基础上,对未来的研究方向及目标提出了建议