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101.
A facile colloidal approach to synthesize Ag8(Ge1?x,Snx)(S6?y,Sey) nanocrystals (NCs) in a highly controlled way across the entire compositional ranges (0≤x≤1, 0≤y≤6) has been developed. The NCs exhibit a uniform size distribution, highly crystalline structure, over 1 g scalable synthesis, and tunable band gaps in the range of 0.88–1.45 eV by varying their chemical compositions. The Ag8GeS6 NCs with a band gap of approximately 1.45 eV were employed as a model light harvester to assess their applicability in solar cells by a full solution‐processing device, yielding an efficiency of 0.28 % under AM1.5 illumination, demonstrating their application potential in solar energy utilization.  相似文献   
102.
本文通过乳液聚合法制备磁性离子印迹材料Fe3O4@SiO2@IIM,并运用多种技术手段对其进行了表征。所制备的Fe3O4@SiO2@IIM磁材料颗粒较均一,粒径约为20nm,单分散性好,具有超顺磁性(饱和磁化强度为8.66emu·g-1)。基于此,建立了离子印迹磁固相萃取(IIMSPE)-石墨炉原子吸收光谱法(GFAAS)联用技术分析环境水样中Ni(Ⅱ)的新方法。对影响MSPE的因素进行了详细的考察。在最优实验条件下,方法对Ni(Ⅱ)的检出限为0.015ng·mL-1,相对标准偏差(RSDs)为7.3%(n=7,c=0.1ng·mL-1),富集倍数为24.8,所制备的磁性离子印迹材料不同批次间RSDs为10.9%(n=5,c=0.1ng·mL-1),所合成的材料可以重复使用5次以上。采用该方法分析了标准水样(GSBZ50009-88)中的Ni(Ⅱ)含量,验证方法的准确性,测定值和标准值吻合良好。将该方法应用于东湖水和长江水中Ni(Ⅱ)的测定,加标回收率为90.6%~107.2%。  相似文献   
103.
Zhang  Jian  Wang  Yi-Yan  Sun  He  Li  Shao-Yu  Xiang  Shao-Hua  Tan  Bin 《中国科学:化学(英文版)》2020,63(1):47-54
A catalytic enantioselective three-component Ugi reaction was developed. SPINOL-derived phosphoric acid with bulky 2,4,6-tricyclohexylphenyl groups at the 6,6′ positions was found to be the best catalyst to afford α-amino amide derivatives in good to excellent yields(62% to 99%) and enantiocontrol(81% to 99% enantiomeric excess). This asymmetric reaction was applicable well to an array of aliphatic aldehydes. The gram-scale synthesis, modification of dapsone, and enantioselective synthesis of(R)-Lacosamide underline the general utility of this methodology. Influence of dihedral angles and substituents of the chiral phosphoric acids on the enantioselectivity was also discussed in this article.  相似文献   
104.
用于数字电视的盲均衡技术研究   总被引:3,自引:3,他引:0  
对目前在接收端采用均衡技术时常用的CMA算法和子空间算法的原理和性能进行了详细的讨论和说明,并给出各自的适用场合.  相似文献   
105.
106.
Functionalized magnetite nanoparticles (Fe3O4) were prepared using the coprecipitation method followed by functionalization with a multipotent antioxidant (MPAO). The MPAO was synthesized and analyzed using FTIR and NMR techniques. In this study, the functionalized nanoparticles (IONP@AO) were produced and evaluated using the FTIR, XRD, Raman, HRTEM, FESEM, VSM, and EDX techniques. The average determined particle size of IONP@AO was 10 nanometers. In addition, it demonstrated superparamagnetic properties. The magnitude of saturation magnetization value attained was 45 emu g−1. Virtual screenings of the MPAO’s potential bioactivities and safety profile were performed using PASS analysis and ADMET studies before the synthesis step. For the DPPH test, IONP@AO was found to have a four-fold greater ability to scavenge free radicals than unfunctional IONP. The antimicrobial properties of IONP@AO were also demonstrated against a variety of bacteria and fungi. The interaction of developed nanoantioxiants with biomolecules makes it a broad-spectrum candidate in biomedicine and nanomedicine.  相似文献   
107.
Egg white protein (EWP) is susceptible to denaturation and coagulation when exposed to high temperatures, adversely affecting its flavour, thereby influencing consumers’ decisions. Here, we employ high-voltage cold plasma (HVCP) as a novel nonthermal technique to investigate its influence on the EWP’s flavour attributes using E-nose, E-tongue, and headspace gas-chromatography-ion-mobilisation spectrometry (HS-GC-IMS) due to their rapidness and high sensitivity in identifying flavour fingerprints in foods. The EWP was investigated at 0, 60, 120, 180, 240, and 300 s of HVCP treatment time. The results revealed that HVCP significantly influences the odour and taste attributes of the EWP across all treatments, with a more significant influence at 60 and 120 s of HVCP treatment. Principal component analyses of the E-nose and E-tongue clearly distinguish the odour and taste sensors’ responses. The HS-GC-IMS analysis identified 65 volatile compounds across the treatments. The volatile compounds’ concentrations increased as the HVCP treatment time was increased from 0 to 300 s. The significant compounds contributing to EWP characterisation include heptanal, ethylbenzene, ethanol, acetic acid, nonanal, heptacosane, 5-octadecanal, decanal, p-xylene, and octanal. Thus, this study shows that HVCP could be utilised to modify and improve the EWP flavour attributes.  相似文献   
108.
109.
Alhagi camelorum (AC) is an old plant with a significant therapeutic value throughout Africa, Asia, and Latin America. The overuse of cisplatin (Cis > 50 mg/m2) is associated with observed nephrotoxicity, ototoxicity, gastrotoxicity, myelosuppression, and allergic reactions. Remedial measures are needed for the protection of nephrotoxicity against cisplatin. Thus, we investigated the nephroprotective effects of AC plant extract to prevent cisplatin-induced nephrotoxicity in albino Wistar rats. The presence of polyphenols, phenolic compounds, tannins, and saponins was revealed during phytochemical investigation, and a significantly intense antioxidant activity was recorded. There were no toxicological symptoms in the treated rats, and no anatomical, physiological, or histological abnormalities were found compared to the control rats. The results of correcting cisplatin-induced nephrotoxicity revealed that the extract has a significant ability to treat kidney damage, with most parameters returning to normal after only three weeks of therapy. It is concluded that co-administration of cisplatin with AC extract showed exceptional nephroprotective effects at a dose of 600 mg/kg for Cis-induced nephrotoxicity.  相似文献   
110.
Liu  Yang  Cai  Jianchao  Sahimi  Muhammad  Qin  Chaozhong 《Transport in Porous Media》2020,133(2):313-332
Transport in Porous Media - During waterflooding, spontaneous imbibition is a fundamental recovery mechanism in fractured reservoirs. A large number of numerical and experimental studies have been...  相似文献   
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