Preparation of pure gum raw materials-low brown algae application

Octenylsuccinate starch ester, also called pure gum, is non-toxic and odourless modified starch which is widely used in many food fields. This study synthesized pure gum in a reaction kettle using the low molecular weight trehalose and octenyl succinic acid. An orthogonal test was carried out to find how the reaction factors affect the synthetization of octenylsuccinic acid polysaccharide ester and to optimize the reaction at single factor level. The optimal products were obtained using 1:2 of octenylsuccinic acid:alginic acid, catalysed by 0.1% p-toluenesulfonic acid catalyst for 1.5 h at 200℃ under vacuum conditions.The gained product contains up to 46% of seaweed gel monoesters. The degree of esterification of the polysaccharide is controlled by the use of the small-molecule trehalose. Compared with the traditional methods, our process can reduce raw material cost and improve emulsification stability of pure gum. These all can significantly improve the market competitiveness of pure gum products.     

西北地区陆地生态系统植被状态参数业务化遥感研究

植被指数(NDVI)和叶面积指数(LAI)是两个非常重要的陆地生态系统植被状态参数.我们首先利用最大值(MVC)合成方法使用先进遥感数据如MODIS、AVHRR3等得到旬合成植被指数(NDVI),然后利用最新的经验方法针对不同的陆地生态系统类型反演得到叶面积指数,重点研究了我国沙尘暴发生频率较高的我国西北地区植被覆被状态及其变化情况.植被指数能够反映区域,乃至全球范围植被年季状态,用于监测陆地生态系统植物光合作用活动及其变化.植被指数作为一个基础参数能够用于计算反演更高级别的陆地生态系统状态参数.叶面积指数直接影响植被的光合作用,蒸腾作用的变化和陆面过程的能量平衡状态.在沙尘暴预测研究中使用的起沙过程模型需要将叶面积指数作为一个关键输入变量,另外,绝大多数生态过程模型模拟碳、水循环时也都需要将叶面积指数作为一个非常重要的输入变量.我们总结了最新的叶面积指数经验反演方法,针对6钟不同的陆地生态系统类型应用不同经验模型计算得到了叶面积指数.     

风云三号A星(FY-3A)的主要性能与应用

我国的气象卫星发展计划始于上世纪70年代,它包括极轨和静止两个系列卫星,以及相应的地面应用系统。气象卫星由航天科技集团公司负责组织研发,第二代极轨气象卫星系列的第一颗星--风云三号A星(FY-3A)于2008年5月27日在太原卫星发射中心成功发射,它又如太空中的一个流动气象观测站,对地球-大气进行全天候、全天时、三维、定量、多光谱的不间断观测。卫星观测资料通过地面加工处理后生成各类产品数据,例如,大气温度和湿度随高度的分布及变化、云参数、雪和冰、大雾、气溶胶、臭氧、辐射等,可用于气象、气候、农、林、牧业、海洋、水文等多领域。风云三号A卫星数据和产品可通过多种方式向用户提供使用。两年来,在奥运、汛期、生态和自然灾害监测中发挥了重要作用。风云三号A星已是世界气象组织全球对地观测系统的重要成员,不仅为我国经济社会提供服务,同时也服务于世界各国。本文综合性地介绍了我国第二代极轨气象卫星系列首发星的主要特点,分析了可能的应用领域,并给出代表性的产品和应用实例。     

Fast CO2 Retrieval Using a Semi-Physical Statistical Model for the High-Resolution Spectrometer on the Fengyun-3D Satellite

China's Fengyun-3D meteorological satellite launched in December 2016 carries the high-resolution greenhouse- gases absorption spectrometer (GAS) aimed at provi...     

一次东风波暴雨过程诊断分析

利用常规气象资料和NCEP 1°×1°再分析资料,结合自动站加密资料对2009年9月29日20:00至10月1日20:00发生在浙江东部沿海的一次东风波暴雨过程进行了分析.结果发现:0916号台风"凯萨娜"外围环流为此次东风波的形成提供了扰动作用,副热带高压的加强使得低层形成了明显的东南急流,为暴雨或强降水的发生提供了...     

攀枝花太阳能资源评价

为了有效地开发和利用攀枝花太阳能资源,本文在广泛搜集国内相关地区太阳辐射资料的基础上,整理了攀枝花几十年的太阳能相关气象数据,通过天文辐射量、日照百分率、经纬度、水汽压等因子建立相关辐射量计算模式,系统地分析和研究了攀枝花地区太阳能辐射量的主要分布特征和优势,对大力开发利用攀枝花太阳能资源提供了科学依据,并就如何发展特色农业和旅游业等综合开发利用方面提出了具体可行的对策建议。      

海洋环境要素极值的加权融合概率模型

如何有效利用海洋环境要素多种来源资料建立其极值概率模型,是实际工程中常遇到的问题.根据海洋环境要素母体子样与其极值子样之间的关系,讨论了现场子样的确定,并推导了其一致性检验方法和计算公式.结合前人对于通过一致性检验的数据进行深入分析建立了数据的可信度概念及其计算方法的研究结果,建立了先验环境要素资料的可信度计算方法.在此基础上结合加权融合方法,建立了海洋环境要素极值的加权融合概率模型,从而使可用信息得到充分利用.通过模拟算例和实际数据验证了一致性检验方法和加权融合概率模型的合理性.     

CCLID不完全复位噪声及复位噪声的消除

本文采用两次复位的方法解决了“不完全复位噪声”的消除问题;在综合分析1728CCLID输出级的复位噪声源的基础上,应用相关概念分析了CDS抑制技术的物理基础、实现条件及要解决的实际问题;据此设计出了比传统的CDS电路性能优越、实用、可完全消除1728CCLID复位噪声的CDS电路。     

A New Method for the Non-destructive Determination of Fish Freshness by Nuclear Imaging

A new method for determining the freshness of harvested carp using nuclear imaging technology is presented. This research attempted to determine the freshness of carp by measuring the radioactive area increase （RAI） value of fish. The carp samples were maintained under refrigerated condition for 12 d, and RAI and total volatile base nitrogen （T-VBN） values were determined during the storage. The results showed that the RAI value increased with the T-VBN content during the storage. Also, there is a significant correlation between T-VBN content and RAI value of the carp kept in refrigerated condition. The results of this study suggest that the RAI value could be utilized to evaluate rapidly the freshness of carp.     

Carbonate Sequence Stratigraphy of a Back-Arc Basin： A Case Study of the Qom Formation in the Kashan Area, Central Iran

The Qom Formation comprises Oligo-Miocene deposits from a marine succession distributed in the Central Basin of Iran. It is composed of five members designated as A-F. Little previous work exists on the sequence stratigraphy. Based on an integrated study of sequence stratigraphy with outcrop data, wells and regional seismic profiles, the Qom Formation is interpreted as a carbonate succession deposited in a mid-Tertiary back-arc basin. There are two second-order sequences (designated as SS1 and SS2) and five third-order sequences (designated as S1-S5). Five distinct systems tracts including transgressive, highstand, forced regressive, slope margin and lowstand have been recognized. The relationship between the sequences and lithologic sub-units has been collated and defined (S1 to S5 individually corresponding to A-C1, C2-C4, D-E, the lower and upper portions of F); a relative sea level change curve and the sequence stratigraphic framework have been established and described in detail. The coincidence of relative sea level change between that of the determined back-arc basin and the world indicates that the sedimentary cycles of the Qom Formation are mainly controlled by eustatic cycles. The variable combination of the systems tracts and special tectonic-depositional setting causally underpin multiple sequence stratigraphic framework styles seen in the carbonates of the back-arc basin revealing: (1) a continental margin basin that developed some form of barrier, characterized by the development of multiple cycles of carbonate-evaporites; (2) a flat carbonate ramp, which occurred on the southern shelf formed by the lack of clastic supply from nearby magmatic islands plus mixed siliciclastics and carbonates that occurred on the northern shelf due to a sufficient clastics supply from the land; and (3) a forced regressive stratigraphic stacking pattern that occured on the southern shelf and in basin lows due to the uplifting of the southern shelf. Thick and widespread aggradational framework limestone usually occurs in the initial sequences (S1 and S3) of the supersequence, which led to preferential oil reservoir deposition but a lack of source and cap rocks, whereas the retrogradational and progradational framework limestone usually occurs in the later sequences (S2 and S4-S5) of the supersequence, which results in two perfect sets of source, reservoir and cap rock assemblies, so that the limestone in sub-member C2-C4 and the F-Member can be predicted as important objects for oil exploration.