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991.
Since red blood cells (RBCs) lack nuclei and organelles, cell membrane is their main load-bearing component and, according to a dynamic interaction with the cytoskeleton compartment, plays a pivotal role in their functioning. Even if erythrocyte membranes are available in large quantities, the low abundance and the hydrophobic nature of cell membrane proteins complicate their purification and detection by conventional 2D gel-based proteomic approaches. So, in order to increase the efficiency of RBC membrane proteome identification, here we took advantage of a simple and reproducible membrane sub-fractionation method coupled to Multidimensional Protein Identification Technology (MudPIT). In addition, the adoption of a stringent RBC filtration strategy from the whole blood, permitted to remove exhaustively contaminants, such as platelets and white blood cells, and to identify a total of 275 proteins in the three RBC membrane fractions collected and analysed. Finally, by means of software for the elaboration of the great quantity of data obtained and programs for statistical analysis and protein classification, it was possible to determine the validity of the entire system workflow and to assign the proper sub-cellular localization and function for the greatest number of the identified proteins.  相似文献   
992.
李晟  戴连奎 《光散射学报》2011,23(3):188-194
拉曼光谱体现了物质中不同分子基团的振动情况,可以精确地进行物质的定性和定量分析.凭借着这样的优势,拉曼光谱技术已经成功应用在化工生产、管道传输、生化反应监测等工业在线分析领域.然而,在线拉曼分析很容易受到宇宙射线的干扰.宇宙射线在拉曼谱图上体现为一系列峰宽较窄的尖锐的峰,也被称为spike.这些spike使待测物质的拉...  相似文献   
993.
Noise map validation by continuous noise monitoring   总被引:1,自引:0,他引:1  
This paper presents a comparison of two noise assessments in the Gdansk agglomeration in Poland. One is based on the noise map produced by computational method for the city in 2007, the second one is based on real data from continuous measurements acquired by a noise monitoring network operating in the city since 2008. Differences are shown and analyzed. Additionally, seasonal and weekday influence on noise indicators (LDEN, LD, LE and LN) is analyzed and discussed in this paper.  相似文献   
994.
 采用固态高温烧结反应方法,成功合成出了陨硅镍铁石样品(Fe0.03Ni0.97)8(Si0.79P0.21)3。X射线衍射结果表明,合成样品的结构为R3'c,对应的晶胞参数为a=b=0.663 8(1) nm,c=3.789 2(2) nm,V=1.446 15(6) nm3。在室温下,对样品进行原位高压X射线衍射研究,实验最高压力达到21.3 GPa,随着压力的升高,晶胞体积逐渐减小,但并没有观察到结构相变。利用Birch-Murnaghan状态方程对体积与压力的关系进行拟合,获得常温常压下的体积V0=1.441 4(24) nm3,体积模量K0=220(7) GPa。晶轴与压力的关系利用Murnaghan状态方程拟合,获得a轴和c轴的模量分别为Ka=257(9)和Kc=165(4),c轴较a轴容易压缩。  相似文献   
995.
 利用分离式霍普金森压杆(Split Hopkinson Pressure Bar,SHPB)技术,研究了土体在不同应变率条件下的冲击动态力学性能,发现土体有明显的应变率效应,与静载相比,冲击载荷下土的动强度和动模量均有很大的提高。根据实验曲线的特征,以一根线性弹簧和两个不同松弛时间的Maxwell体并联的粘弹性模型来表达土体的损伤型粘弹性本构模型,两个Maxwell体分别表示土体的低应变率响应和高应变率响应,模型的数值拟合曲线与实测动态本构曲线具有较好的一致性。拟合参数表明,土体对低应变率的响应与混凝土相同,对高应变率的敏感性远远高于混凝土。  相似文献   
996.
激光辐照环境对金属材料反射特性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
 利用积分球绝对测量法,对在20 Pa真空缺氧、1 000 Pa空气,105 Pa空气及1 000 Pa氧气环境下,1 064 nm波长连续激光辐照30CrMnSiA碳钢材料过程中的反射光信号进行了测量,得到了30CrMnSiA碳钢在4种辐照环境下的反射率和温度变化曲线。结果表明:在空气组分辐照环境的低压到105 Pa范围内,材料初始反射率随压力增大而增大;在缺氧和富氧环境的激光辐照过程中,缺氧环境下材料反射率变化缓慢,且变化拐点温度高于富氧环境,富氧环境下材料被加热后的快速氧化反应有利于材料对激光能量的吸收;不同辐照环境(缺氧和富氧)相同材料温度条件下,材料反射率并不相同。  相似文献   
997.
水中镉含量的激光诱导击穿光谱高灵敏快速检测   总被引:1,自引:0,他引:1       下载免费PDF全文
 为了对水中的痕量镉进行高灵敏快速检测,实验采用一种未受污染的薄木片作为基底来吸收水样品,将其晾干后再用激光诱导击穿光谱(LIBS)技术对其进行分析,克服了用LIBS技术直接分析水样品时灵敏度低和稳定性差等问题。实验中选择214.44 nm的镉离子线作为分析线以提高光谱检测的灵敏度,建立了用于定量分析的校正曲线,镉的检出限达到55 μg/L,重复测量的信号相对标准偏差小于5%,单次测量的时间短于5 min。  相似文献   
998.
Additive Ba(N 3) 2 as a source of nitrogen is heavily doped into the graphite-Fe-based alloy system to grow nitrogendoped diamond crystals under a relatively high pressure (about 6.0 GPa) by employing the temperature gradient method.Gem-grade diamond crystal with a size of around 5 mm and a nitrogen concentration of about 1173 ppm is successfully synthesised for the first time under high pressure and high temperature in a China-type cubic anvil highpressure apparatus.The growth habit of diamond crystal under the environment with high degree of nitrogen doping is investigated.It is found that the morphologies of heavily nitrogen-doped diamond crystals are all of octahedral shape dominated by {111} facets.The effects of temperature and duration on nitrogen concentration and form are explored by infrared absorption spectra.The results indicate that nitrogen impurity is present in diamond predominantly in the dispersed form accompanied by aggregated form,and the aggregated nitrogen concentration in diamond increases with temperature and duration.In addition,it is indicated that nitrogen donors are more easily incorporated into growing crystals at higher temperature.Strains in nitrogen-doped diamond crystal are characterized by micro-Raman spectroscopy.Measurement results demonstrate that the undoped diamond crystals exhibit the compressive stress,whereas diamond crystals heavily doped with the addition of Ba(N 3) 2 display the tensile stress.  相似文献   
999.
BC5 is a newly synthesized superhard material. We present a systematic investigation of optical properties of BC5 in P3m1 and I-4m2 phases at ambient and high pressure in the framework of density functional theory with the generalized gradient approximation (GGA) in this paper. Optical properties such as dielectric function, refractive index, absorption, reflectivity and electron energy-loss spectrum are obtained successfully. The feature in the spectra of the optical parameters is discussed. Through calculation, we find BC5 is optically anisotropic. Moreover, the dielectric function exhibits a large change at 70 GPa pressure for P3m1 BC5 phase, but I-4m2 phase not, indicating the stable electronic structure that the I-4m2 phase possesses.  相似文献   
1000.
This work is concerned with the theoretical study of the combined effects of applied electric field and hydrostatic pressure on the binding energy and impurity polarizability of a donor impurity in laterally coupled double InAs/GaAs quantum-well wires. Calculations have been made in the effective mass and parabolic band approximations and using a variational method. The results are reported for different configurations of wire and barriers widths, impurity position, and electric field and hydrostatic pressure strengths. Our results show that for symmetrical structures the binding energy is an even function of the impurity position along the growth direction of the structure. Also, we found that for hydrostatic pressure strength up to 38 kbar, the binding energy increases linearly with hydrostatic pressure, while for larger values of hydrostatic pressure the binding energy has a non-linear behavior. Finally, we found that the hydrostatic pressure can increase the coupling between the two parallel quantum-well wires.  相似文献   
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