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1.
Yun-Yun Tang Hou-Yu Wang Lu Chen Si Li Chen-Gang Guo Hui-Zhi Fan Cheng-Xi Cao Liu-Yin Fan 《Analytical and bioanalytical chemistry》2013,405(26):8587-8595
We developed a novel polyacrylamide gel electrophoresis (PAGE) method to stack and separate human hemoglobins (Hbs) based on the concept of moving reaction boundary (MRB). This differs from the classic isotachophoresis (ITP)-based stacking PAGE in the aspect of buffer composition, including the electrode buffer (pH 8.62 Tris–Gly), sample buffer (pH 6.78 Tris–Gly), and separation buffer (pH 8.52 Tris–Gly). In the MRB-PAGE system, a transient MRB was formed between alkaline electrode buffer and acidic sample buffer, being designed to move toward the anode. Hbs carried partial positive charges in the sample buffer due to its pH below pI values of Hbs, resulting in electromigrating to the cathode. Hbs would carry negative charges quickly when migrated into the alkaline electrode buffer and be transported to the anode until meeting the sample buffer again. Thus, Hbs were stacked within a MRB until the transient MRB reached the separation buffer and then separated by zone electrophoresis with molecular sieve effect of the gel. The experimental results demonstrated that there were three clear and sharp protein zones of Hbs (HbA1c, HbA0, and HbA2) in MRB-PAGE, in contrast to only one protein zone (HbA0) in ITP-PAGE for large-volume loading (≥15 μl), indicating high stacking efficiency, separation resolution, and good sensitivity of MRB-PAGE. In addition, MRB-PAGE was performed in a conventional slab PAGE device, requiring no special device. Thus, it could be widely used in separation and analysis of diluted protein in a standard laboratory. Figure
Diagram of MRB-induced stacking in a slab PAGE. (A) arrangement of separation buffer (pH 8.01–9.55 Tris–Gly), sample buffer (pH 6.37–7.22 Tris–Gly), and electrode buffer (pH 8.21–9.05 Tris–Gly); (B) initial MRB formed between electrode and sample buffers for stacking of low-content Hbs in sample buffer under electric field; (C) MRB moving toward the anode and partly stacking of Hbs within the MRB; (D) quasi-complete stacking of Hbs via MRB closing to the separating gel; (E) separation of Hbs in a zone electrophoresis mode 相似文献
2.
Microstructure evolution and passivation quality of hydrogenated amorphous silicon oxide(a-SiOx:H) on〈100〉- and 〈111〉-orientated c-Si wafers
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Hydrogenated amorphous silicon oxide(a-SiOx:H) is an attractive passivation material to suppress epitaxial growth and reduce the parasitic absorption loss in silicon heterojunction(SHJ) solar cells. In this paper, a-SiOx:H layers on different orientated c-Si substrates are fabricated. An optimal effective lifetime(τ(eff)) of 4743 μs and corresponding implied opencircuit voltage(iV(oc)) of 724 mV are obtained on〈100〉-orientated c-Si wafers. While τ(eff) of 2429 μs and iVoc of 699 mV are achieved on 111-orientated substrate. The FTIR and XPS results indicate that the a-SiOx:H network consists of SiOx(Si-rich), Si–OH, Si–O–SiHx, SiO2 ≡ Si–Si, and O3 ≡ Si–Si. A passivation evolution mechanism is proposed to explain the different passivation results on different c-Si wafers. By modulating the a-SiOx:H layer, the planar silicon heterojunction solar cell can achieve an efficiency of 18.15%. 相似文献
3.
研究了衬底温度对MOCVD技术制备的ZnO薄膜的微观结构和光电特性影响. XRD和SEM的研究结果表明,衬底温度对ZnO薄膜的微观结构有显著影响,明显的形貌转变温度大约发生在175℃,低于175℃,薄膜呈镜面结构,晶粒为球状,高于177℃的较高温度范围,薄膜从“类金字塔”状的绒面结构演化为“岩石”状显微组织;随着温度增加,薄膜的晶粒尺寸明显增大.绒面结构的未掺杂ZnO薄膜具有17.96 cm2/V·s的高迁移率和3.28×10-2 Ω·cm的低电阻率,对ZnO薄膜的进一步掺杂和结构优化有望应用于Si薄膜太阳电池的前电极.
关键词:
MOCVD
ZnO薄膜
透明导电氧化物
太阳电池 相似文献
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采用RF-PECVD技术,通过改变反应气体的硅烷浓度制备了一系列不同晶化率不掺杂的硅薄膜材料,研究了工艺变化对材料结构的影响及材料光电特性同微结构的关系.随后进行了光衰退试验,在分析光照前后光电特性变化规律的基础上,认为材料中的非晶成分是导致材料光电特性衰退的主要原因.在靠近过渡区非晶一侧的硅材料比普通非晶硅稳定,衰退率较少;高晶化率微晶硅材料性能稳定,基本不存在光衰退;在靠近过渡区微晶一侧的硅材料虽然不是完全不衰退,但相比高晶化率硅材料来说更适合制备高效微晶硅电池.
关键词:
射频等离子体增强化学气相沉积
硅薄膜
Staebler-Wronski(SW)效应
稳定性 相似文献
6.
NMR, potentiometric, and UV/VIS measurements were run to study the protonation and the In3+ and Cu2+ stability constants of 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (do3a, L). The protonation of do3a follows the typical scheme with two high and several low log KH values. Between pH 11 and 13, the protonation mainly occurs at the N-atom, which is not substituted by an acetate side chain. The In3+ complex is not appreciably protonated even at low pH values (pH ? 1.7), whereas [CuL] can add up to three protons in acidic solution to give the species [CuLH], [CuLH2], and [CuLH3], the stability of which was determined. The formation rates of the Y3+, Gd3+, Ga3+, and In3+ complexes with do3a were measured using a pH-stat technique, whereas that of Cu2+, being faster, was followed on a stopped-flow spectrophotometer. In all cases, the reaction scheme implies the rapid formation of partially protonated intermediates, which rearrange themselves to the final product in the rate-determining process. ([MLH])in, an intermediate, in which the metal ion probably is coordinated by two amino acetate groups, proved to be the reactive species for Y3+, Gd3+, and Ga3+. The formation of [Cu(do3a)] was interpreted by postulating that either ([CuLH])in or ([CuLH])in, and ([CuLH2])in are the reactive complexes. The rates of dissociation of the Y3+, Gd3+, and Cu2+ complexes with do3a were studied spectrophotometrically. For Y3+ and Gd3+, arsenazo III was used as a scavenger, whereas for Cu2+ the absorption associated with d-d* transition was followed. For [Y(do3a)] and [Gd(do3a)], the rate law follows the kinetic expression kobsd ? k0 + k1[H+]. The dissociation of [Cu(do3a)] goes through the proton-independent dissociation of [CuLH3], which is the main species at low pH. 相似文献
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The stability constants of the Mn2+, Zn2+, Ni2+, pb2+, and Cd2+ complexes with 1,4,7-triazacylononane-1-acetic acid (noma) were determined at 25° and 0.5M (KNO3) by potentiometric titrations. The species [ML] and [ML(OH)] were found in al cases except for Ni2+, whereas [ML2] was only detected for Cd2+. For the complexes [ML], the order of stability is Mn2+ < Cd2+ < pb2+ < Zn2+ < Zn2+ < Ni2+ < Cu 2+, which is consisten with the Irvin-Williams Series. 相似文献
8.
在毛细管超薄池光度检测中首次采用吸收光强测量新技术,显著提高了测量的灵敏度和改善了信噪比。在内径50μm的石英毛细管超薄池以及由石英光导纤维构成的十字交叉超薄光学吸收池上,分别测量了系列高锰酸钾溶液吸收光强。吸收光强与高锰酸钾溶液浓度之间呈现良好的线性关系。对于10μg/mL的高锰酸钾稀溶液,毛细管超薄池吸收光强测量的信噪比相对于吸光度测量的有较大的改善。十字交叉池的光程约为40μm,容积约为0.02μL,具有较大的光能量,可望发展成为一种新型的电泳光度检测池。 相似文献
9.
以Pb2+和S-腺苷甲硫氨酸(S-Adenosylmethionine,SAM)与聚3-(1-(2-三乙胺乙酰基)哌啶-4-亚甲基)噻吩(poly 3-{[1-(2-hydrazino-2-oxoethyl)piperidin-4-ylidene]methyl}thiophene,PMTH)构建荧光开关,当有Pb2+存在时,PMTH与Pb2+之间发生作用,荧光猝灭,即为荧光"关";当Pb2+-PMTH体系中加入SAM时,SAM能够与Pb2+形成更稳定的配合物,使PMTH的荧光恢复,即为荧光"开"。通过PMTH的荧光开关信号,成功建立了识别和检测SAM的新方法。研究了在水-乙醇(4∶1,V/V)溶液中Pb2+和PMTH与SAM相互作用对荧光光谱的影响。本方法具有很好的灵敏度和选择性,常见氨基酸和金属离子对SAM的检测无影响,在最佳实验条件下,SAM的浓度在1.0×10-8~2.0×10-6mol/L范围内与相对荧光强度呈线性相关,线性回归方程为ΔI=68.51+72.32C(μmol/L),相关系数r=0.9982,检出限为8.72×10-9mol/L;本方法已成功用于SAM检测。 相似文献
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