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关键词： Sesame stalks   broad bean stalks   biomass chips   bubbling fluidized bed combustion   combustion characteristics   emissions  

摘要： The study work investigated the combustion characteristics and gaseous emissions during burning chips of sesame and broad bean stalks in a pilot-scale Bubbling Fluidized Bed Combustor (BFBC). The effects of the startup temperature, excess air percentage, moisture content, and injection location of secondary air on axial temperature profiles along the combustor and flue gas emissions were studied. The results indicated that biomass fuel characteristics have a significant role in the distribution of axial temperature along the reactor height. A great effect on the axial temperature profile was detected when the startup temperature was changed. The 30% and 100% excess air represent the near percentages for better combustion characteristics for burning the stalks of broad bean and sesame, respectively. Enhancement was observed in the combustion behavior when using the dried samples compared to the as-received samples. Higher values of axial temperature and lower concentrations of flue gas emissions are a result of rising injection location of the secondary air. The combustion efficiency reached to 92.4% for burning the sesame stalks and 96.6% for the broad bean stalks. Based on an energy balance performed on the BFBC, the thermal efficiency was ranged from 28.2% to 59.4% for SS and from 17.2% to 42.1% for broad bean stalks.

关键词： 碳—氧同位素   主—微量元素   碳酸盐胶结物   平台地区   柴达木盆地  

摘要： 综合运用岩石学、矿物学以及元素地球化学等理论,对柴达木盆地北缘构造带中段平台地区古近系路乐河组(E1+2)储集岩的岩石学特征、碳酸盐胶结物、黏土矿物以及沉积成岩环境进行分析研究。结果表明:平台地区路乐河组储集岩主要为岩屑砂岩和长石岩屑砂岩,储集岩内颗粒之间以点—线接触关系为主,少量为线接触关系;孔隙类型以原生粒间孔为主,其次为粒内溶蚀孔隙;黏土矿物含量较高,平均值达到了21.92%,主要以伊—蒙混层、伊利石、蒙脱石和绿泥石为主,具有明显的蒙皂石向伊—蒙混层转化的特征。碳—氧同位素分析结果显示碳同位素值(δ13C)在-8.87‰^-3.91‰之间,平均为-5.66‰,碳来源主要为脱羧作用的有机质碳和碳酸盐岩中的无机碳,淋滤作用也造成胶结物中δ13C值变低;氧同位素值(δ18O)介于-12.97‰^-8.75‰,平均值为10.68‰,推算其古盐度Z值分布范围在103.79~114.27之间,平均为110.38,碳酸盐沉淀温度分布范围在62.89℃~90.53℃之间,平均为75.20℃;通过全岩的微量元素分析表明,U/Th、V/Cr、Ni/Co以及Cu/Zn均反映出温暖、湿润的成岩环境,古盐度、Sr/Ba与U值也指向淡水沉积环境,说明平台地区路乐河组储集岩主要形成于温暖湿润的淡水沉积环境之中。

关键词： 顺北地区   走滑断裂   流体特征   地球化学   储层发育模式  

摘要： 塔里木盆地顺北油田在上奥陶统覆盖区的非暴露条件下,沿走滑断裂发育大量缝洞储集体。通过高精度三维地震和测井资料分析,结合钻井、录井及生产动态数据,研究认为,塔里木盆地顺北地区的储集空间类型主要为沿深大断裂带的断面发育且受溶蚀改造的大型洞穴或断面空腔,其次为断裂破碎带内的砾(粒)间缝、砾(粒)内缝、高角度构造缝以及伴生的溶蚀孔洞。储层受通源主干走滑断裂带控制,横向非均质性强,但纵向连通性好,断裂面是储层发育的有利部位。主干走滑断裂具有明显的分段性,且断裂带内部结构复杂,发育交织的多重断层核部结构,直接影响着储层的展布。通过岩石学和地球化学综合分析认为,储层最主要的改造流体以通源走滑断裂导致的上行深埋成岩-成痉流体为主,局部存在热液流体成岩改造特征。通源走滑断裂贯穿了层序界面、岩性界面以及热液流体运移界面等多套具备储层物质基础的地层,形成了顺北地区纵向连通性强,横向可延展的规模储集体。

关键词： 无阀   压电泵   阻流体   绕流阻力   微混合器  

摘要： 针对生物、化学、医学、航空等领域混合输送微流体、微流体介质的需要,提出了集流体混合、泵送为一体的复合阻流体无阀泵,并借助复合阻流体致涡实现涡致混合功能。基于流体绕流原理对绕流阻力进行了全新诠释和表达;并利用“尾流空间压强比较法”和“流体单元动量分析法”进行了绕流复合阻流体的阻力分析,揭示了复合阻流体致阀及其本质性成因;改变传统无阀泵的结构,通过引入分流环和复合阻流体,减少泵回流量的同时实现了涡致混合的功能。制作了泵样机,在驱动频率为11 Hz、电压为180 V条件下进行了泵流量试验和流体混合试验,其瞬时流量达到53.7 mL/min;同时,借助流体涡的运动较好地混合了流体,试验验证了新型泵具有混合及泵送流体的功能。新型泵的提出创新和丰富了无阀泵的结构和功能,为无阀泵应用于微流体混合传输领域奠定了基础。

关键词： 蜂窝状结构   表面反射   气体压力   肥皂泡   表面张力   表面积  

摘要： 在气体压力和表面张力的共同作用下,肥皂泡要在体积不变的前提下努力使表面积最小,故而大部分时候呈球形。而当多个肥皂泡挤在一起时,就会形成不规则的蜂窝状结构。从肥皂泡薄膜上下表面反射回来的阳光会发生干涉,让有些颜色的光减弱,有些颜色的光增强,所以我们看到的肥皂泡是彩色的。

关键词： 稠密惰性元素   结合能   原子团簇理论   多体展开方法   从头算方法   压缩特性  

摘要： 基于量子理论和原子团簇理论,运用多体展开方法和第一性原理的从头算方法,提出了一种计算稠密惰性元素(氦、氖、氩和氪)原子结合能的新势函数,运用新公式研究了结合能对高压稠密惰性元素高压压缩特性的影响。此公式引入了一个物理参量β(其值为0.5),使得势函数的表达形式更加简单、准确。对比结果表明,结合能的新势函数能够准确地描述多体相互作用对结合能的贡献,且平均相对误差在5%以内。结合能的新势函数对压缩特性的影响在当前实验压强范围内(氦60 GPa、氖238 GPa、氩114 GPa、氪128 GPa)做出了令人满意的描述,且与实验值及理论计算结果基本完全吻合,平均相对误差在3%以内。最后,以固氩的压强数据为例,验证了势函数的准确性。该势函数不仅适用于更宽密度和更高压强范围,而且对所有惰性元素原子各种状态的结合能、高压压缩特性、定容比热容、熔化曲线和弹性模量的研究具有重要的指导意义。

关键词： 减水剂   分散   表面张力   吸附量  

摘要： 研究了8种减水剂对拌和水表面张力和减水剂吸附特性对减水剂分散速率的影响.结果表明:除氨基磺酸盐系高效减水剂(ASF)会略微提高拌和水表面张力外,其余7种减水剂均能有效降低拌和水表面张力,聚羧酸系减水剂(PCE)侧链特性是影响拌和水表面张力的决定因素,而酸醚比的影响较小;萘系高效减水剂(NSF),ASF和脂肪族高效减水剂(SAF)的吸附量显著高于5种PCE,在较高掺量条件下,ASF和SAF会发生脱附,PCE中吸附基团(—COO^-)质量分数越高,吸附量越大;提高搅拌速率和延长搅拌时间可以提高PCE的分散效果,但对NSF、ASF和SAF的作用有限;拌和水表面张力降低并不能提高减水剂分散效果的发挥速率,而NSF、ASF、SAF和23PCE4因具有相对较高的吸附量,表现出较大的初始分散效果,但其余4种PCE并未表现出此对应关系.

关键词： Ash deposition   Circulating fluidized bed combustion   Oil shale semi-coke   Sodium scavenging   Zhundong lignite  

摘要： Scavenging of sodium and ash deposition characteristics during co-combustion of Zhundong lignite with an oil shale semi-coke in a circulating fluidized bed (CFB) were investigated. Zhundong lignite (ZD) and its blends with the semi-coke (SC) of 10 and 20 wt% were combusted in the CFB furnace at 950 degrees C. Two air-cooled probes were placed in the furnace chamber (P-1) and at the cyclone outlet (P-2), respectively, to simulate ash deposition. The bottom ash, fly ash and ash deposits on the probes were collected and analysed by using XRD, SEM-EDX, ICP-OES and laser particle analyser. Results show that the fly ash burning ZD was comprised of sub-micron particles and agglomerates enriched in CaSO4 and SiO2, with Na being NaAlSi3O8, Na2SiO3, Na2Si2O5 and NaAlSiO4. When SC of high Si/Al was added, the fly ash was comprised of sub-micron particles with less agglomerates, where Na-bearing minerals were also evidently reduced. Likewise, the bottom ash was coarse-grained particles rich in SiO2, (Ca, Na)(Si, Al)(4)O-8 and CaSiO3 during ZD combustion but changed to SiO2, (Na, Ca) Al(Si, Al)(3)O-8 or NaAlSi3O8 as SC was added, suggesting that Na was captured by SC and retained in the bottom ash. The deposit on P-1 was enriched in Na2SO4 and CaSO4 when ZD was burned but turned into coarse-grained particles rich in Ca/Na aluminosilicates while SC presented, showing a decreased sintering propensity. Likewise, the P-2 deposit was of Ca/Na sulphates agglomerates, but became refractory SiO2, Ca sulphate and aluminosilicates as SC added. Ash deposition in CFB burning ZD is consequently mitigated with SC addition.

关键词： 表面张力   平板法   铂金板   可替换性  

摘要： 分析了平板法测液体表面张力的测试原理,概括了DCAT21表面张力仪平板法测液体表面张力的测试过程,从理论上分析了国产铂金板代替进口铂金板的可行性。通过实验,证明了国产铂金板可用在DCAT21表面张力仪上进行日常测试,测试值与理论值偏差不超过0.2%。