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71.
Journal of Russian Laser Research - We design a miniaturized and highly-sensitive biosensor based on a photonic-crystal aslant cavity (AC) to detect protein concentrations. The AC has seven ring... 相似文献
72.
Nonlinear Dynamics - In recent years, substantial work has been done for developing image encryption algorithms. Image encryption requires handling of large data, which needs computationally... 相似文献
73.
Jyoti Tiwari Swastika Singh Mohammad Saquib Fatima Tufail Amit Kumar Sharma Shailesh Singh 《合成通讯》2018,48(2):188-196
The discovery of a new L-valine promoted facile and versatile green synthesis of diversified 2-amino-3-cyano-4H-pyrans using a one pot multicomponent-tandem reaction of aromatic aldehydes, malononitrile, and diverse electron-rich enolizable carbonyl compounds is described. To the best of our knowledge this is the first report on the use of native L-valine as a catalyst in organic synthesis. Environmental friendly, mild reaction conditions, use of easily available inexpensive starting materials, short reaction time, excellent yields, high atom economy, and recyclability of organocatalyst are the major advantages of the disclosed protocol. 相似文献
74.
Zoubeïda Khefacha Zohra Benzarti Mohamed Mnari Mohamed Dachraoui 《Journal of Crystal Growth》2004,260(3-4):400-409
Cd1−xZnxS films with 0x0.18 were grown by chemical bath deposition technique on glass substrates from an aqueous solution containing cadmium and zinc sulfate, ammonia and thiourea. Microstructural features, obtained from X-ray diffraction and scanning electron microscopy (SEM) measurements, reveal a predominance of Wurtzite structure and an homogenous microstructure formed by densely microcrystallines for all the samples studied. Cd1−xZnxS semiconductor was found to be resistive and of n-type. Also, the electron density decreases with increased x and the mobility reaches a maximum around x=0.12. Which means that the Cd1−xZnxS films at this composition are of high crystalline quality, i.e. having reduced intrinsic defect concentrations. 相似文献
75.
Fatima Erragh Ali Boukhari Brahim Elouadi Elizabeth M. Holt 《Journal of chemical crystallography》1991,21(3):321-326
Na2CoP2O7 may be prepared in two allotropie forms:I, rose,M
r
=278.85, triclinic, P1,a=9.735(2),b=10.940(3),c=12.289(4) Å,=148.78,=121.76(1), =68.38(2)°,V=566.8(2) Å3,Z=4,D
meas=3.28(5) g cm–3,D
calc=3.267 g cm–3, (MoK)=0.71069 Å,=37.12 cm–1, F(000)=540,T=298 K,R=5.4% for 2911 observed reflections; andII, blue,M
r
=278.85, orthorhombic, P21cn,a=7.713(2) Å,b=10.271(4),c=15.378(6)°,V=1218.2(8) Å3,Z=8,D
meas=3.06(5) g cm–3,D
calc=3.040 g cm–1, (MoK
) Å,=34.55 cm–1, F(000)=1080,T=298 K,R=9.9% for 1450 observed reflections. Cobalt displays octahedral coordination to six oxygen atoms in the rose form whereas the metal coordination is tetrahedral in the blue form. 相似文献
76.
Vladimir T. Abaev Fatima A. Tsiunchik Alexander V. Butin Andrey V. Gutnov 《Journal of heterocyclic chemistry》2008,45(2):475-481
77.
Piotr Smoleński M.Fatima C. Guedes da Silva Armando J.L. Pombeiro 《Journal of organometallic chemistry》2008,693(13):2338-2344
The water-soluble RhI compound [Rh(Tpms)(CO)(PTA)] (1) (Tpms = O3SC(pz)3−, PTA = 1,3,5-triaza-7-phosphaadamantane) has been easily prepared in high yield by a single-pot reaction of [{Rh(CO)2(μ-Cl)}2] with PTA and the tris(1-pyrazolyl)methanesulfonate lithium salt Li(Tpms), in a CH2Cl2/MeOH solution at room temperature. This synthetic strategy can be easily applied to the preparation of general [Rh(Tpms)(CO)(L)] (L = phosphine) complexes and constitutes a substantial improvement over the previously described procedures. Compound 1 is air stable in the solid state and water-soluble, affording stable solutions under an inert atmosphere. It has been characterized by IR, 1H, 31P{1H} and 13C{1H} NMR spectroscopies, elemental and single crystal X-ray diffraction structural analyses. The solid state structure of 1 has a square-planar geometry with the Tpms ligand coordinating the metal centre in a (κ2: N,N) bipodal mode. The title compound has also been investigated by cyclic voltammetry in CH3CN, and values of the EL Lever and PL Pickett electrochemical parameters (which measure the ligand net electron-donor character) are proposed for the PTA ligand. Complex 1 represents the first example of a transition metal complex bearing both PTA and Tpms (or any other tris(1-pyrazolyl)methane or derivative) ligands. 相似文献
78.
Muhammad Saeed Aswa Firdous Muhammad Saleh Zaman Fatima Izhar Mubeshar Riaz Sabah Haider Muzamil Majeed Shahzaib Tariq 《中国化学会会志》2023,70(4):789-824
Nowadays, desulfurization of fuel oil has raised concern globally because of strict industrial and environmental legislations. Albeit hydrodesulfurization (HDS) has been extensively used in oil refineries to produce low sulfur oil (< 10 ppm) but not been proven as effective method for the removal of dibenzothiophene (DBT), benzothiophene (TH) and their derivatives. Subsequently, adsorptive desulfurization (ADS) and oxidative desulfurization (ODS) methods have been developed to achieve high removal efficiency. In the past decade, metal–organic frameworks (MOFs) and its composites as oxidative catalysts, as well as adsorbents, have attracted the researchers owing to high surface area, tunable properties, and reusable. The present review comprises use of MOFs and their composites for the removal of sulfur from fuel oil via ODS and ADS processes. Additionally, physicochemical properties of MOFs, mechanism, pros and cons of both process, regeneration, and future challenges have been discussed briefly. Moreover, current limitations and future prospective are also discussed. 相似文献
79.
The electron donor-electron acceptor (acid-base properties) of cell surfaces of a series of bacteria were determined by two methods, namely, Microbial Adhesion to Solvents (MATS) and Contact Angle Measurements (CAM) combined with equation of Van Oss. The efficiency of these two methods was then compared. Pseudomonas aeruginosa ATCC 27853, Bacillus subtilis ILP 142B, Staphylococcus aureus ATCC 25923 and four Escherichia coli strains including HB101, AL52, O128B12 and ATCC 25922, acid-base properties were examined under the two different conditions mentioned above. The results showed that the correlation between acid-base properties determined by MATS and CAM was very weak. We have also found that when the microbial cell surface was electron donor by CAM method, similar result was found by MATS, but the reverse was not always true. In contrast, a good correlation between the two methods was obtained when the four E. coli strains were examined. 相似文献
80.
Zaheer Ahmad Itrat Fatima Sajid Mehmood Rehana Ifzal Abdul Malik Nighat Afza 《Helvetica chimica acta》2008,91(1):73-78
Three new 20,24‐epoxydammarane triterpenes, santolins A–C ( 1 – 3 ), were isolated from the AcOEt‐soluble fraction of the MeOH extract of Salvia santolinifolia (whole plant). Their structures were assigned based on 1H‐NMR, 13C‐NMR (DEPT), and 2D‐NMR analyses, in combination with HR‐MS experiments and comparison with literature data of related compounds. 相似文献