19 research outputs found
Comparison between REA model and thin layer drying model based on strip drying kinetics
为了获得最适用于烟草干燥的动力学模型,达到设计、优化和控制烟草干燥过程的目的,采用湿度发生器联用热重技术(TGA)研究了65 ℃ &RH; 15%, 75 ℃ & RH 10%和85℃& RH 5%条件下片烟的干燥动力学行为,并利用REA (Reaction engineering; approach)以及8种经验或半经验的薄层干燥模型分别对不同温湿度条件下的片烟干燥行为进行模拟。结果表明:①干燥温度越高,相对湿度越小时,片烟; 的干燥速率越快,平衡含水率越低;②REA模型预测的片烟干燥动力学曲线与实验曲线能够很好地吻合,尤其是在含水率由20%降至12%阶段;8种薄层干燥; 模型中Two; term模型拟合出的R~2值最大,均方根误差(RMSE)最小,是描述片烟干燥行为较合适的模型;③薄层干燥模型仅仅是获得特定温湿度条件下相对应的动; 力学参数,而REA模型是将温度和湿度作为变量引入模型中,模型中的动力学参数可以描述任意温湿度条件下的片烟干燥动力学行为;④REA模型构造简单,预; 测准确快速,较Two term模型更具有普适性、实用性。In order to select a kinetic model best fit for the design, optimization; and control of tobacco drying process, the drying kinetic behavior of; tobacco strips under the conditions of 65 ℃ & RH 15%, 75 ℃ & RH10%, 85 ℃; & RH 5% was investigated with a humidifier combined with TGA; (Thermogravimetric analyzer). The drying behavior of tobacco strips was; simulated by REA (Reaction engineering approach) model and eight; selected thin layer drying models (semi-empirical or empirical). The; results showed that: 1) With the rise of temperature and decrease of; humidity, the drying rate of strips raised and the equilibrium moisture; content of strips lowered. 2) The drying kinetic curves predicted by REA; model well agreed with experimental curves, especially at the stage when; the moisture content decreased from 20% to 12%. Among eight thin layer; drying models, Two term model was the best for predicting the drying; behavior of strips with the highest R~2 (determination coefficient) and; the lowest RMSE (root mean square error). 3) Thin layer drying model; reflected only the kinetic parameters corresponding to specified drying; conditions, while in the REA model the temperature and humidity served; as variables, it enabled the kinetic parameters in REA model to describe; the drying kinetic behavior at any drying condition. 4) REA model was; simple in structure, fast and accurate in prediction, more universal and; practical than Two term model.福建中烟工业有限公司科技项
Effects of heating rate on fast pyrolysis of cut filler of cigarette
为考察升温速率对卷烟烟丝快速热解行为的影响,采用热重-质谱联用技术对卷烟烟丝在不同升温速率(200 K·min~(-1)~800 K·min~(-1))下的热解特性进行研究,并建立了不同升温速率下卷烟烟丝的快速热解动力学模型。结果表明:(1)随着升温速率的升高,烟丝各主要成分热分解温度区间的叠加程度、热解速率以及释放特性指数均呈递增趋势,且有不同程度的热滞后现象。(2)引入升温速率校正因子的动力学模型能够克服热滞后所引起的动力学参数偏差,可以更好地预测不同升温速率下卷烟烟丝的快速热解行为。(3)高升温速率下,热解烟气产物中质荷比(m/z)为56(丙烯醛)、79(吡啶)、84(烟碱)、94(苯酚)和117(吲哚)的化合物释放量减小。在高升温速率下卷烟烟丝的快速热解特性与卷烟燃烧的真实状态更为接近,建立的卷烟燃烧数学模型更加准确。In order to study the effects of heating rate on fast pyrolysis of cut filler of cigarette, TGA(Thermogravimetric Analyzer) combined with QMS(Quadrupole Mass Spectrometers) was applied to investigate the pyrolysis characteristics of cut filler of cigarette at different heating rates(200 K·min~(-1)-800 K·min~(-1)), and a kinetic model for the fast pyrolysis of cut filler at different heating rates was developed. The results showed that: 1) With the increase of heating rates, thermal decomposition overlap region, mass loss rate and devolatilization index of each main component in tobacco were raised. Meanwhile, thermal lags of different extents were also observed. 2) The kinetic model overcame the deviation of kinetic parameters caused by thermal lag via introducing a heating rate correction factor, and predicted the fast pyrolysis behaviors of cut filler at different heating rates more accurately. 3) The release of pyrolysis products, such as acrolein(m/z=56),pyridine(m/z=79), nicotine(m/z=84), phenol(m/z=94) and indole(m/z=117) decreased with the increase of heating rate. The fast pyrolysis characteristics of cut filler are closer to the real state of cigarette combustion and the developed mathematical model for tobacco pyrolysis kinetics is more accurate at high heating rate.福建省中烟工业有限责任公司科技创新项目“卷烟燃烧数学模型的建立及其在卷烟减害中的应用”(FJZYJH2013025
吐哈油田水淹层剩余油精细评价技术研究与应用
该项目针对吐哈三大主力油田自身的地质特点,提出了一系列适用的水淹层解释方法和图版,正自然电位高压油层理论和岩性系数法解释水淹层属国内首创。本次研究是在以岩电实验为前提的水淹机理等基础研究的基础上,开展水淹层特征及其定性、半定量、定量解释等水淹层测井解释方法研究和剩余油评价方法研究,并将研究的阶段成果及时应用于调整井测井解释和老井挖潜工作中,由此检验研究成果的有效性和存在问题,进而对研究成果进行补充完善。研究成果经实际应用检验,水淹层测井解释符合率达到85%
THE APPEARANCE FEATURES AND ENVIRONMENTAL INDICATION OF SURFACE SEDIMENTS IN CHUKCHI SEA AND CANADA BASIN
通过对中国首次和第二次北极科学考察采集的表层沉积物的观察,根据沉积物的颜色和气味、砾石分布、底栖生物及贝壳分布特征的分析,探讨了该海区表层沉积物表观特征变化与有机质输入、沉积物的氧化还原状态的关系、底栖生物分布范围、冰筏碎屑的分布区域及与海流的关系,指出在研究区软体动物生长的北界位于73.5°N,比浮游动物的北界约低2个纬度。冰筏碎屑的北界可作为融冰水的北界或永久冰区的南界,位置在77°24′N附近。通过对沉积物表观特征的综合分析,结合研究区的海流特征,指出研究区的海流分布对沉积物分布有重要影响,尤其是两股不同性质的海流相遇,对西南部与东部两个区域的沉积物组成及性质具有较强的控制作用。The apparent features of surface sediments collected during Chinese First and Second Arctic Research Expedition were observed.Based on the recognition of color and odor of the sediments,distribution of gravels or ice-rafted debris and molluscan remains in the surface sediments,we discuss the relation among the apparent features of surface sediments and the content of organic matters,oxidation-reduction status as well as the distribution range of benthos,ice-rafted detritus and the relation with ocean current.We find that the north boundary of mollusks is located at 73.5°N,which is 2° lower than that of zooplanktons.The north boundary of ice-rafted detritus which is also the north boundary of melting water and equals to the south boundary of permanent ice region,appears near 77°24'N.According to analysis of apparent features of sediments,combining with current characteristics in study area,we conclude that current plays an important role in distribution of sediments,especially for that within the southwest region and east region.国家自然科学基金项目(40576060,40376017
Benthic foraminiferal assemblages in the western Arctic surface sediments and their paleoenrivonmental implications
通过对中国第1~4次北极考察在西北冰洋采集的表层沉积物中底栖有孔虫丰度及其优势种分布特征与环境因素关系的综合研究发现,楚科奇海区低的底栖有孔虫丰度主要受较高的陆源物质输入的稀释作用影响;楚科奇海台和阿尔法脊较高的底栖有孔虫丰度主要受到暖而咸的大西洋中层水的影响;受碳酸钙溶解作用影响的门捷列夫深海平原和加拿大海盆底栖有孔虫丰度较低,并且水深3 597M的站位出现了似瓷质壳的PyrgO WIllIAMSOnI和QuInQuElOCulInA OrIEnTAlIS,说明该区的CCd深度大于3 600M。根据底栖有孔虫7个优势属种的百分含量分布特征可以划分出5个区域组合:南楚科奇海陆架-白令海峡组合以优势种ElPHIdIuM EXCAVATuM和buCCEllA frIgIdA为特征,可能反映受白令海陆架水影响的浅水环境;阿拉斯加沿岸-波弗特海组合以优势种flOrIluS SCAPHuS和ElPHIdIuM AlbIuMbIlICATuM为特征,可能反映受季节性海冰融化,低盐的阿拉斯加沿岸流以及河流淡水输入的低盐环境;大西洋中层水组合以优势种CASSIdulInA lAEVIgATA为特征,可能反映高温高盐的大西洋中层水影响的环境;北极深层水组合以优势种CIbICIdES WuEllErSTOrfI为特征,可能反映水深大于1 500M低温高盐的北极深层水环境;门捷列夫深海平原组合以优势种OrIdOrSAlIS uMbOnATuS为特征,可能反映低营养的底层水环境。Benthic foraminiferal assemblages in 139 western Arctic surface sediment samples recovered during the CHINAREⅠ~Ⅳcruises were studied.The relative abundances of each species were calculated and according to the spatial distribution pattern of dominant species,benthic foraminiferal assemblages were divided to determine the relationship between the assemblage and environmental parameters.Our results show that the spatial distribution pattern of low benthic foraminiferal abundance in the Chukchi shelf area is controlled by high terrigenous matter input.In Chukchi Plateau and Alpha ridge,high benthic foraminiferal abundance is influenced by the warm and saline intermediate Atlantic water.In the Mendeleev Abyssal Plain and Canadian Basin,low benthic foraminiferal abundance is influenced by calcium carbonate dissolution and the appearance of porcelain-like species Pyrgo williamsoni and Quinqueloculina orientalis at 3 597 msites indicates the carbonate compensate depth(CCD)is greater than3 600m.Five assemblages related to spatial environmental factors can be determined by 7 dominant species:Southern Chukchi shelf-Bering Strait assemblage is dominantly characterized by Elphidium excavatumand Buccella frigida,representing the influence of shallow Bering Sea Shelf Water;Alaska Coast-Beaufort Sea assemblage is dominantly characterized by Florilus scaphus-Elphidium albiumbilicatum,indicating the low salinity environment due to seasonal sea ice melting and/or Alaska Coastal Current or riverine input;Atlantic Intermediate Water assemblage is dominated by Cassidulina laevigata,representing warm saline Atlantic Intermediate Water;Arctic Deep Water assemblage is dominated by Cibicides wuellerstorfi,reflecting the low temperature and high salinity environment greater than 1 500m;Mendeleev Abyssal Plain assemblage is dominated by Oridorsalis umbonatus,showing the oligotrophic bottom water environment.国家自然科学基金重点项目(41030859); 南北极环境综合考察与评估专项——2012年度北极海域海洋地质考察(CHINARE2012-03-02); 中国地质调查局项目(水[2012]01-011-05
HOLOCENE BIOMARKER RECORDS ON THE NORTHERN BERING SEA SLOPE AND THEIR PALEOENVIRONMENTAL IMPLICATIONS
通过白令海北部陆坡区b2-9站位沉积物柱样高分辨率的生物标志物(菜子甾醇、甲藻甾醇、长链烯酮、n-C30-dIOl)提取和分析,获得了近1万年来浮游植物群落和初级生产力、高碳烷烃输入与陆源植被变化等相关记录,研究结果显示,全新世以来表层浮游植物和初级生产力都经历了“高-低-高“的变化过程,并具有明显的阶段性,可能受控于陆架坡折处海冰的分布、上层海洋营养盐供应和全新世气候与环境的变迁;浮游植物群落结构较为稳定,硅藻是初级生产力的主要贡献者,甲藻次之,颗石藻和黄绿藻比前两者低了1个数量级,硅藻与甲藻之间具有明显的竞争关系,前者明显占据优势,是白令海有机碳汇的主要贡献者;正构烷烃总量分别在7.8 kA bP,6.7 kA bP和5.4 kA bP,经历了3次阶梯状的下降过程,并呈现出4个相对稳定的阶段,其主要受控于早全新世海平面上升以及周边陆地植被源区的气候与环境变化;正构烷烃分子组合特征显示其来自陆地高等植物、且陆源植被结构较为稳定,木本植物占据优势;单体碳同位素研究表明正构烷烃的主碳峰为n-C27,对烷烃总量的贡献最大,可能与当时陆源繁盛的木本植物及输入有关,含量较高的n-C23则可能主要来源于北半球沿海广泛分布的一类沉水植物。Variations in phytoplankton community and primary productivity,plus input of terrestrial high-carbon nalkanes and vegetation changes in their source during the last 9.6 ka are investigated based on extraction and measurement of high-resolution biomarkers(brassicasterol,dinosterol,n-C37-alkenone,n-C30-diol) at Site B2-9 on the northern Bering Sea Slope.The results show that surface phytoplankton and primary productivity have undergone obvious periodic changes from high to low and back to high during the Holocene,which might have been controlled by sea-ice expansion on the shelf-break,nutrient supplementation at the sea surface,and climate change.Diatoms were the greatest contributors to primary productivity,followed in turn by dinoflagellates,coccolithophores and eustigmatophytes.The abundance of eustigmatophytes was an order of magnitude lower than those of dinoflagellates and coccolithophores in the steady phytoplankton community.In the clear competitive relationship between diatoms and dinoflagellates,the former had an obvious advantage,and formed the major input to organic carbon sinks in the Bering Sea.Furthermore,the stepwise total n-alkanes dropped quickly at 7.8 ka BP,6.7 ka BP and 5.4 ka BP, indicating that there were four relatively stable stages,which might have been controlled by sea-level rise during the early Holocene and environmental changes in the terrestrial vegetation source surrounding the Bering Sea.The molecular parameters indicate that the n-alkanes originated from terrestrial higher plants with a stable vegetation structure,and woody plants dominated in this type of assemblage.Mono-carbon isotopic results show that the n-C27content was the main carbon peak and dominated the total n-alkanes,which might be related to the abundance of woody plants in the vegetation source and their spatial distribution.The higher n-C23content may have been mainly derived from submerged plants,which are widely distributed along coastal areas in the northern hemisphere.国家自然科学基金重点项目(41030859)、国家自然科学基金中俄合作与交流项目(41211120173); 南北极环境综合考察与评估专项(CHINARE2013-03-02;CHINARE2013-04-01); 国家海洋局极地考察办公室对外合作支持项目(IC201105); 中国地质调查局地质调查工作项目(水[2013]02-013-012)资
LATE QUATERNARY PALEOCEANOGRAPHIC RECORDS IN THE SOUTHERN OKHOTSK SEA
鄂霍次克海是太平洋第二大边缘海,在西北太平洋水文环境中扮演重要角色。综合分析了鄂霍次克海南部T00孔沉积物的多种替代性指标,揭示了鄂霍次克海晚第四纪以来的环境变化受季节性海冰变化、大气循环模式、陆源物质通量和表层生产力的共同影响。对比放射虫CyClAdOPHOrA dAVISIAnA的含量曲线与lr04氧同位素记录,该孔沉积物可划分为氧同位素1-7期,底部年龄约为250kA。C.dAVISIAnA在间冰期的高含量表明鄂霍次克海中层水是北太平洋中层水的主要源区。蛋白石和有机碳的分析显示鄂霍次克海表层生产力在冰消期突然增大,随后在间冰期逐渐下降,冰期普遍较低。C/n比值曲线的分析说明鄂霍次克海的有机质沉积物主要来源于海洋。沉积物粒度的分析揭示鄂霍次克海冰期时陆源粗颗粒含量较低,至冰消期粗颗粒含量突然增加,而在间冰期陆源粗颗粒含量较高。The Sea of Okhotsk is the second largest marginal sea of the Pacific,and plays a significant role in the hydrology of the northwestern Pacific.We processed and analyzed multi-proxies of the sediment of core T00 from the southern Sea of Okhotsk.The results show that the environmental changes in the Sea of Okhotsk are characterized by a coupled interplay between seasonal sea ice dynamics,atmospheric circulation patterns,terrigenous flux,and surface productivity during late Quaternary.The stratigraphic MIS1 to MIS7 since--250 ka of core T00 has been recognized by comparing the percentage curve of Cycladophora davisiana with the LR04 benthic δ18O stack.The higher percentage of C.davisiana during interglacial intervals indicates that the Sea of Okhotsk is the source region of the North Pacific Intermediate Water Mass.The primary productivity in the southern Sea of Okhotsk,indexed by contents of opal and total organic carbon,is relatively higher during interglacials than during glacials,and increases rapidly during deglacials.The oceanic origin of the organic matters in core T00 is figured out by the C/N ratio analysis.The content of terrigenous coarse grain in the Sea of Okhotsk is lower in glacials than in interglacials and increases rapidly in deglacials.国家重点基础研究发展规划项目(G2007CB815903);国家自然科学基金项目(40321603;40676030;40576029);高等学校博士学科点专项科研基金(20040247028
Biogenic and terrigenous coarse fractions in surface sediments of the western Arctic Ocean and their sedimentary environments
通过中国第1至第3次北极科学考察在北冰洋西部所采集的99个表层沉积物中生源与陆源粗组分的分析,研究了该海域表层生产力的变化,有机质来源以及陆源粗颗粒物质的输入方式和影响因素。研究区域生源组分所反映的表层生产力变化与通过白令海峡进入楚科奇海的3股太平洋洋流密切相关。楚科奇海西侧高盐高营养盐的阿纳德尔流流经区域,表层生产力普遍较高;东侧低盐低营养盐阿拉斯加沿岸流流经区域,浮游硅质生物生产力低,并且受陆源有机质输入影响显著。阿尔法脊和楚科奇海台较高的浮游钙质生物生产力与北大西洋水的注入密切相关。楚科奇海陆架区低的浮游钙质生物生产力与陆源物质的稀释作用和浮游钙质生物生活水深有关;加拿大海盆区低的浮游钙质生物生产力主要受到碳酸钙溶解作用的影响。研究区域表层沉积物中的陆源粗组分-冰筏碎屑(ICE-rAfTEd dETrITuS,Ird)的分布主要受海冰和冰山的搬运,陆缘冰输入,河流输入以及太平洋入流水的影响。白令海峡入口处的陆源粗颗粒沉积主要受太平洋入流水影响;阿拉斯加近岸海域的陆源粗颗粒沉积来自于陆缘冰以及河流的输入;而北风脊高的Ird含量主要是由海冰和冰山所携带,被波弗特环流搬运至此,伴随着海冰和冰山的融化并卸载进入沉积物中。Biogenic and terrigenous coarse fractions in the surface sediments from the western Arctic Ocean,which were collected in the First,the Second and the Third Chinese National Arctic Expeditions,were measured by different means in this paper,revealing the surface productivity changes,source of organic matter and input patterns of terrigenous coarse matters in the study area.The surface productivity indicated by the biogenic sediments in the area is closely related to the three Pacific Ocean currents entering into the Chukchi Sea through Bering Strait.High surface productivity in the western Chukchi Sea is resulted from the hyperhaline and hypertrophic Anadyr Stream,whereas low planktonic siliceous productivity in its eastern part is caused by the hypohaline and hypotrophic Alaska Coastal Stream.High planktonic calcareous productivity in the Chukchi Sea Plateau and Alpha Ridge is ascribed to the impact of the northern Atlantic water mass.Low planktonic calcareous productivity in the Chukchi Sea shelf is attributed to the terrigenous matter dilution and life depth of calcareous microorganism.Low calcareous planktonic productivity in the Canada Basin is responded to the strong CaCO3 dissolution.Distribution of terrigenous coarse fraction(ice-rafted detritus-IRD) in the western Arctic Ocean is influenced mainly by sea ice and iceberg transport,terrestrial ice input,river and Pacific currents.The terrigenous coarse fraction in the Bering Strait is impacted by the Pacific currents entering into the Chukchi Sea through Bering Strait.The terrigenous coarse fraction near Alaska coastal area is transported by the terrestrial ice and river.The high IRD in the Northwind Ridge is contributed by the massive sea ice and icebergs conveyed by the Beaufort Circulation,and deposited at the seafloor when the sea ice and icebergs melt.国家重点基础研究发展规划项目(G2007CB815903);国家自然科学基金重点项目(41030859);中国第3次北极科学考察以及国际极地年中国行动计划资助项目;中国地质调查局项目(水[2010]矿评03-06-04