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991.
《印度化学会志》2023,100(8):101051
The FT-IR, FT-Raman, UV–Vis and NMR spectra of 4-Hydroxy-3-nitrobenzaldehyde (4H3NB) were examined by the hybrid correlation approach. B3LYP method with 6–311++G(d,p) basis set were utilised to obtain the ideal molecule form, vibrational wavenumbers, Raman activities and infrared intensities. The vibrational spectra's detailed interpretation was to be provided by the MOLVIB software. Bonding orbitals participate in all stages of natural bond orbital (NBO) analysis as donors and acceptors, which stabilises molecules through intermolecular charge transfer. Electron localization function (ELF) and localised orbital locator (LOL) maps were used to create 4H3NB and have topological properties. The title molecule's interactions were examined via reduced density gradient (RDG) evaluation. Molecular docking research was used to foreseen the binding interactions of 4H3NB derivative with the estrogen receptor 4-hydroxybenzaldehyde. Auto-dock software was used to conduct receptor-ligand docking investigation. According to the molecular docking results, the highest mean negative binding affinity (−6.718 kcal/mol) was exhibited by the current chemical.  相似文献   
992.
Lateral flow immunoassay (LFIA) is a rapid, simple, and inexpensive point-of-need method. A major limitation of LFIA is a high limit of detection (LOD), which impacts its diagnostic sensitivity. To overcome this limitation, we introduce a signal-enhancement procedure that is performed after completing LFIA and involves controllably moving biotin- and streptavidin-functionalized gold nanoparticles by electrophoresis. The nanoparticles link to immunocomplexes forming multilayer aggregates on the test strip, thus, enhancing the signal. Here, we demonstrate lowering the LOD of hepatitis B surface antigen from approximately 8 to 0.12 ng mL−1, making it clinically acceptable. Testing 118 clinical samples for hepatitis B showed that signal enhancement increased the diagnostic sensitivity of LFIA from 73 % to 98 % while not affecting its 95 % specificity. Electrophoresis-driven enhancement of LFIA is universal (antigen-independent), takes two minutes, and can be performed by an untrained person.  相似文献   
993.
The heterogeneous catalytic oxidation of Chromotrope 2B (C2B) dye with H2O2 and the aluminum oxide hydroxide (AlOOH) modified with ammonia complexes of CuII, CoII, NiII, and CrIII (AlOOH/[Mn+(amm)m]) as catalysts were studied. The AlOOH/[CuII(amm)4] is the most efficient catalyst and therefore it was chosen as the potential catalyst for the oxidative degradation of C2B in an aqueous solution. The AlOOH/[CuII(amm)4] was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM), techniques. The rate of reaction was dependent on the type of the metal complex supported on the AlOOH, initial concentration of the dye and H2O2, catalyst dose, pH, the concentration of NaCl, and temperature. The catalytic activity of the AlOOH/[Mn+(amm)m] according to the kind of metal ion decreased in the order: CuII > CoII > CrIII > NiII. Other catalysts consisting of the AlOOH supported with CuII complexed with ethylenediamine, ethanolamine, 1,3 propanediamine, and 1,4 butanediamine, (AlOOH/[CuII(amine)m]), were also investigated. The activity of the (AlOOH/[CuII(amine)m]) as catalyst according to the type of ligand followed the order: 1,4 butanediamine > 1,3 propanediamine > ethanolamine > ethylenediamine > ammonia. The reaction rate increased with increasing the catalyst dose, concentration of H2O2, C2B, and NaCl, pH, and temperature. Since the reusability results for the AlOOH/[CuII(amm)4] revealed good stability over seven cycles, it can thus be considered a promising and cost-effective catalyst for the removal of harmful dyes from wastewater.  相似文献   
994.
Aflatoxin determination is imperative among agricultural and food products as the pollution of the toxic aflatoxin could cause severe hazards towards animals and human beings. Here, we prepared Elaeagnus gum derived porous carbon material as electrode modified material. In situ electropolymerization of molecularly imprinted polymer utilizing phenol as monomer and aflatoxin B1 as target template was further processed onto the porous carbon surface to achieve aflatoxin B1 sensing ability. This sensitive MIP sensor has a detection range from 5 pM to 100 pM of aflatoxin B1, an electrochemical sensitivity of 82.4 μA log(pM)−1 cm−2 with a detection limit of 1.7 pM, and a recovery rate of real sample measurement is 98.21 %. Good selectivity, fair repeatability and stability was confirmed. This work demonstrates the promising application of Elaeagnus gum derived porous carbon modified electrode sensor for food and drug monitoring.  相似文献   
995.
In this study, a hydrostable Z-scheme Ag/CsPbBr3/Bi2WO6 photocatalyst was designed and fabricated for the degradation of Rhodamine B (RhB). The structural instability of CsPbX3 perovskites in water is one of the main obstacles that restrict their practical application in photocatalytic wastewater treatment. The photocatalyst was prepared in three steps: passivation of CsPbBr3 nanocrystals (NCs) with 3-mercaptopropionic acid (MPA), construction of a heterojunction between MPA-passivated CsPbBr3 NCs and Bi2WO6 ultrathin nanosheets, and doping Ag nanoparticles as charge mediators in the heterojunction. The as-obtained 5%Ag/20%CsPbBr3/Bi2WO6 exhibits good stability and excellent photocatalytic activity. The degradation rate is 93.9% in 120 min, which is 4.41 times than that of Bi2WO6.  相似文献   
996.
Two new ent-kaurene diterpenoids, angustifolin B and natural hydrogen-bonded 1:1 complex, angustifolin C, as well as four known diterpenoids, angustifolin, isodonal, sodoponin, tri-chorabdal B, were isolated from the leaves of Rabdosia angustifolia.  相似文献   
997.
应用装有EPM-810Q电子探针扫描分析电镜,对50例乙肝患者头发中Mg、Al、Cd、Ca、Cr、Mn、Fe、Cu、Zn、Pb、Se11种元素含量进行分析,并与健康人头发进行比较。结果表明:乙肝组中Zn含量低于健康组,Cu、Cd、Fe含量高于健康组(P〈0.01)。  相似文献   
998.
碘化物-罗丹明B体系荧光猝灭反应测定痕量亚硝酸根   总被引:8,自引:0,他引:8  
拟定了一个荧光猝灭法测定痕量亚硝酸根的新方法。在盐酸介质中,亚硝酸根氧化 碘化钾的反应,其反应产物I3-使罗丹明B荧光猝灭。方法的检出限为3.6μg/L;测定范围为 10~120μg/L。方法简便快速、选择性好,用于自来水,矿泉水及合成样品中亚硝酸根的测定, 结果满意。  相似文献   
999.
In this paper, we consider some asymptotic models for internal waves in the small amplitude/small amplitude regime, which were derived recently by Bona, Lannes and Saut. We first prove that the Boussinesq/Full dispersion systems and the Boussinesq/Boussinesq systems can be derived from the Full dispersion/Full dispersion systems. Then using a contraction-mapping argument and the energy method, we will prove that the derived systems that are linearly well-posed are in fact locally nonlinearly well-posed in suitable Sobolev classes. In particular, we improve and extend some known results on the well-posedness of Boussinesq systems for surface waves.  相似文献   
1000.
We derive a formula for the density of positive integers satisfying a certain system of inequality, often referred as prime number races, in the case of the polynomial rings over finite fields. This is a function field analog of the work of Feuerverger and Martin, who established such formula in the number field case, building up on the fundamental work of Rubinstein and Sarnak.  相似文献   
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