海黍子中甾醇类化合物的初步研究

从中国青岛海域采集的海洋褐藻海黍子（Sagassum muticum）,经提取和纯化分离后,得到3个甾醇类化合物,经1 H-NMR、13C-NMR和MS等现代光谱手段鉴定,它们的结构分别为：岩藻甾醇（1）、马尾藻甾醇（2）和较为少见的24-乙基-2a-氧杂-2-氧-5α-羟基-3,4-二失碳-24（28）-胆甾烯（3）,这是首次报道的从海黍子马尾藻中分离得到A环降二碳的甾醇类化合物.     

海黍子有性生殖相关形态建成因子分析

为了评估海黍子Sargassum muticum有性繁殖生殖力情况,利用统计学方法对海黍子有性生殖相关的形态建成因子进行了初步研究,通过分析藻体长度与侧枝数、侧枝长度与生殖托数、生殖托长度与生殖托挂卵数之间的数量相关性,利用回归方程估算了海黍子的个体生殖力。结果表明:海黍子成熟藻体平均长度为(164.5±59.9)cm,侧枝平均长度为(10.4±5.3)cm,生殖托平均长度为(9.3±1.5)mm,单个生殖托平均挂卵数量为(378±121)粒,各因子间存在线性正相关性(P<0.05)。研究表明,单株海黍子成熟藻体能够产生(21~400)万粒受精卵,可基本满足1 m~2的采苗生产需要。     

北极礁膜室内人工育苗的研究

于2004年对大连地区北极礁膜M onostroma arcticum的生物学进行了初步研究,并在室内进行了合子采苗、孢子体培养和孢子采苗及幼苗培养等人工育苗试验。结果表明:水温为3℃时,北极礁膜的叶片长度达到16 cm;水温为5℃时,配子放散量达到2.4×108个/g;孢子体在水温低于19℃时生长较快,水温超过22℃时生长几乎停止。孢子体在度过夏季高温期后,当水温降至20℃以下时,开始形成孢子囊;当水温降至15℃时,孢子放散量达到6.1×105个/cm2;孢子附着到苗绳上后经过50 d的室内培养,培育出长度为1 cm的北极礁膜幼苗。     

六带石斑鱼人工育苗的培育技术研究

宁德市蕉城区漳湾镇水技站从2006年至2008年,从台湾购进六带石班鱼受精卵,通过人工育苗,培育出3—5cm健康鱼苗48.8万多尾,其中2008年(8月20日)受精卵孵化率80%;从仔鱼至出苗最高成活率为31.3%;出苗25万多尾,最高出苗量为2666尾/m3。     

室内人工冰场气流组织研究现状与进展

随着2022年北京冬奥会的临近,国内又新建了许多室内人工冰场.文章首先对室内人工冰场结露和起雾的原因做的分析,提出了防结露和除雾的措施.对冰场常见的几种的气流组织方式做了介绍,并阐述了CFD数值模拟技术在室内人工冰场的具体应用.     

岩扇贝人工育苗的初步研究

为丰富中国扇贝养殖品种,利用从加拿大引进的岩扇贝Crassadoma gigantea种贝,采用人工控温的方法于2016年进行室内人工育苗试验。结果表明:种贝室内培育28 d后自然排卵一次,培育至37 d后用联合刺激法催产,获得约4亿个卵,通过人工授精,卵受精率为90%,孵化率为80%,选育出D形幼虫约3.2亿个;幼虫浮游期持续30 d,成活率为31.4%,采苗后附着变态率为13.2%,变态期持续5~10 d;采苗后培养25 d出池进行海上中间育成,存活率为24.2%。研究表明,岩扇贝在大连人工控温室内育苗和海上中间育成具有可行性。     

洁净车间建筑室内装修技术实例

襄樊仪表元件厂为适应发展自动化仪器仪表等新产品的发展需要 ,决定新建集成电路生产线 ,此部分以１０万级洁净生产区为主 ,分为上、下两层 ,底层为线性电路车间 ,二层为数字电路车间 ,洁净区建筑面积为１２１０ｍ２。具有一定空气洁净度要求的房间称为洁净室 ,集成电路大部分生产工序的环境都需要进行空气净化处理。根据工艺流程及其对洁净、恒温等不同要求 ,线性、数字电路车间其洁净等级设计要求为１０万级 ,即粒度在０．５μｍ以上的尘垢含量不得超过３５００个／Ｌ。洁净车间要确保净化环境 ,虽然主要是依赖空气净化即空调手段来实现 ,…     

建筑室内光环境的影响因素研究

本文基于对建筑室内光环境的研究,通过数据测定,软件分析,进而确定影响室内光线的因素,从节能角度对室内光环境的被动式设计提出相应思考和建议,并对该方向未来的研究进行初步探索。     

浅谈林业育苗现状及容器育苗技术

随着我国社会的发展,生态林业也发展越来越快,我国对天然林资源的保护工程实施导致对种苗的需求量越来越多,而对育苗的技术要求也越来越高。本文就我国的林业育苗现状及容器育苗技术做一番简单的阐述。     

有关林木育苗技术的研究综述

文章首先分析了森林育苗常用的几种方法,分别从传统育苗方式、无性繁殖栽培、扦插育苗、组织培育等方面来进行。其次介绍了在育苗期间应用生物制剂的作用,帮助完善森林育苗技术。将其应用在森林培育管理中,能够大幅度提升树木成活率。     

中西方地缘战略理论研究

地缘战略研究为世界主要国家和集团推行其政治、经济、军事、外交战略所重视。西方的地缘战略理论在研究分析国际关系时,重视分析地理因素的影响作用,能够把世界作为一个整体加以分析,具有一定的合理性。中国地缘战略思想异彩纷呈,为追求国家的安全及和平发展、构建和谐世界而不断探索。     

Column biosorption of lanthanum and europium by Sargassum

Batch and column biosorption of La(3+) (lanthanum) and Eu(3+) (europium) was studied using protonated Sargassum polycystum biomass. The ion exchange sorption mechanism was confirmed by the proportional release of protons and by the total normality of the solution, which remained constant during the process. Equilibrium isotherms were determined for the binary systems, La/H and Eu/H for a total normality of 3 meq g(-1), which produced separation factors of 2.7 and 4.7, respectively, demonstrating a higher affinity of the biomass towards europium. Column runs with a single metal feed were used to estimate the intra-particle mass transfer coefficients for La and Eu (6.0 x 10(-4) and 3.7 x 10(-4) min(-1), respectively). Modeling batch and column binary systems with proton as the common ion was able to predict reasonably well the behavior of a ternary system containing protons. The software FEMLAB was used for solving the set of coupled partial differential equations. Moreover, a series of consecutive sorption/desorption runs demonstrated that the metal could be recovered and the biomass reused in multiple cycles by using 0.1N HCl with no apparent loss in the biosorbent metal uptake capacity.     

Elemental and radioactive analysis of commercially available seaweed

Edible seaweed products have been used in many countries, specifically Japan, as a food item. Recently these products have become popular in the food industry because of a number of interesting medicinal properties that have been associated with certain edible marine algae. Very little control exists over the composition of these products, which could be contaminated with a number of agents including heavy metals and certain radioactive isotopes. Fifteen seaweed samples (six local samples from the coast of British Columbia, seven from Japan, one from Norway and one undisclosed) were obtained. All samples were analyzed for multiple elements, using ICP mass spectrometry and for radioactive constituents. It was found that six of eight imported seaweed products had concentrations of mercury orders of magnitude higher than the local products. Lead was found at somewhat higher concentrations in only one local product. Laminaria japonica had the highest level of iodine content followed by Laminaria setchellii from local sources. Only traces of cesium-137 were found in a product from Norway and radium-226 was found in a product from Japan. Arsenic levels were found to be elevated. In order to estimate the effect of these levels on health, one needs to address the bioavailability and the speciation of arsenic in these samples.     

论红色家书的思想政治教育功能

红色家书见证了中国共产党的光荣奋斗历程，蕴含着丰富的红色基因，是进行思想政治教育的重要素材和载体。红色家书的思想政治教育功能主要体现在四大方面：一是凝聚思想功能，即红色家书凝聚着理想信念、爱国力量和民族精神；二是道德示范功能，即红色家书在艰苦奋斗、廉洁奉公、无私奉献等优良道德方面具有示范功能；三是政治引导功能，即红色家书具有指引政治目标、强化政治意识、维护政治稳定的功能；四是情感激励功能，即红色家书具有激发责任意识、激励坚定为民信念、激励斗争精神的功能。充分发挥红色家书的教育功能，有利于增强思想政治教育的实效。     

客土喷播植草施工简介

阐述了客土喷播的基本原理,从边坡清理、测量放线、锚杆施工、挂网施工及客土喷播等方面介绍了高速公路边坡客土喷播植草的施工方法,体现了客土喷播护坡效果好、经济美观且适用范围广的优点,提高了我国公路、铁路等的绿化水平。     

Effect of counterions on lanthanum biosorption by Sargassum polycystum

The effect of the presence of different anions on the biosorption of La(3+) (Lanthanum) using Sargassum polycystum Ca-loaded biomass was studied in this work. Different types of metal salts were used, such as nitrate, sulphate and chloride. The presence of the anion sulphate decreased the metal uptake for tested pH values of 3--5 when compared to the nitrate and chloride systems. The presence of chloride ions did not seem to interfere with the lanthanum removal. The speciation of lanthanum in solution could explain the differences obtained for the different systems and the Mineql+ program was used for the calculations. A monovalent complex with sulphate and lanthanum was formed that had lower apparent affinity towards the biomass compared to the free trivalent metal ion. The La uptake varied from 0.6 to 1.0 mmol g(-1). The Langmuir model was used to describe quantitatively the sorption isotherms. The addition of sulphuric acid for pH adjustment decreased the metal uptake from lanthanum sulphate solutions when compared to the nitric acid addition. The effect was more pronounced with sulphuric acid due to the formation of complexes.     

建筑室内总挥发性有机物成分分析及其对室内空气质量影响

总挥发性有机物是判断室内空气质量的重要指标,在我国《民用建筑工程室内环境污染控制规范》(GB 50325-2001)标准中属于必测的指标。国家标准样品中共含有苯、甲苯、乙酸丁酯等9种物质,而由于其中实际成分权重的问题,导致在实际测试中可能出现由于某种污染物(如乙酸丁酯)毒性较小,但是权重较大,从而使总挥发性有机物接近或超出国家标准;某种污染物毒性较大(如苯),但是权重较小,反而不会超出国家标准。这使判断室内空气质量对人员的影响出现较大的问题。本文通过对实际测试的大量样本的详细分析,发现有些空气样本中乙酸丁酯含量较多,但其毒性较小,故对人的影响远远小于苯系物含量较小的总挥发性有机物。因此,需要进行大量室内污染物现场调研工作,从而对目前国家标准中规定的污染物比例等做出修正。     

Interaction of light metals and protons with seaweed biosorbent

Based on their displacement by protons, the following ascending order of light metals affinity toward Sargassum fluitans biomass was observed: Na⁺ K⁺ < Mg²⁺ < Ca²⁺ < Al³⁺. Higher biomass-metal affinities resulted in lowering the leaching tendency of (polysaccharidic) biomass components during the sorption process. More than 12% weight loss of protonated biomass occurred during 2 min of sorption, which should be considered in all stoichiometric and sorption calculations. The rate of proton uptake for Na-loaded and Ca-loaded S. fluitans biomass at pH 4.5 was lower than the rate of desorption at pH 1.1. In the case of Na-loaded S. fluitans, the predominant proton uptake rate was of a zero order. Na uptake by protonated S. fluitans biomass did not take place at all in the presence of Ca and Al ions. However, it increased in the absence of other light metals. Since the affinity of Ca²⁺ for the biomass was much greater than that of Na⁺, the three-component system of Na⁺, H⁺ and Ca²⁺ could be simplified into proton-calcium ion exchange. The initial rate of Ca uptake with protonated S. fluitans biomass at pH 4.5 was lower than that of proton release from biomass. Approximately 20% of Ca²⁺ sorbed was bound to the binding site as a mono-valent ion. Titration and stoichiometric indications pointed to the fact that Al was being sorbed as a hydroxyl complex.