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101.
Naeem Nida Khoja Asif Hussain Butt Faaz Ahmed Arfan Muhammad Liaquat Rabia Hasnat Amin Ul 《Research on Chemical Intermediates》2022,48(5):2007-2034
Research on Chemical Intermediates - In this study, biomass fly ash (BFA)-supported Ni/CaO catalyst was synthesized, characterized and evaluated for partial oxidation of methane (POM) in a fixed... 相似文献
102.
Muhammad Asim Farooq Md Aquib Sana Ghayas Rabia Bushra Daulat Haleem Khan Amna Parveen Bo Wang 《先进技术聚合物》2019,30(9):2183-2191
Natural polymers have been extensively utilized in the past decades due to their outstanding features. Among these natural excipients, protein‐based polymers have superb features owing to their high drug binding capacity and biodegradability. Whey protein is a versatile protein‐based vehicle for drug delivery systems. It has been shown to be nontoxic, biocompatible, and biodegradable. Therefore, it has been considered as an ideal biomaterial for the design of advanced drug delivery systems. Protein‐based cargo acts as synthetic polymers counterpart for innovative delivery systems. The current review is mainly focused on application of whey proteins as an emerging carrier in drug delivery systems, achieved during the past. 相似文献
103.
Rabia Akhtar Syed Ali Raza Naqvi Ameer Fawad Zahoor Sameera Saleem 《Molecular diversity》2018,22(2):447-501
Aziridine ring opening reactions have gained tremendous importance in the synthesis of nitrogen containing biologically active molecules. During recent years, a great effort has been put forward by scientists toward unique bond construction methodologies via ring opening of aziridines. In this regard, a wide range of chiral metal- and organo-catalyzed desymmetrization reactions of aziridines have been reported with carbon, sulfur, oxygen, nitrogen, halogen, and other nucleophiles. In this review, an outline of methodologies adopted by a number of scientists during 2013–2017 for aziridine ring opening reactions as well as their synthetic applications is described. 相似文献
104.
In this paper we define the Jensen–Steffensen inequality and its converse for diamond integrals. Then we give some improvements of these inequalities using Taylor’s formula and the Green function. We investigate bounds for the identities related to improvements of the Jensen–Steffensen inequality and its converse. 相似文献
105.
Sonogashira cross coupling is a well-known reaction for the formation of carbon–carbon bond. It involves the coupling of aryl halides with terminal alkynes to synthesize versatile functionalized alkyne scaffolds having diverse applications. Many of the natural products and important pharmaceutical drugs can be obtained through this reaction. In this regard, hectic progress has been put by the synthetic chemists to make this cross coupling more effective. This review article discloses mild and environmental friendly reaction conditions of Sonogashira cross coupling developed during 2013–2018. 相似文献
106.
Tariq Mahmud Rabia Rehman Aqsa Gulzar Amina Khalid Jamil Anwar Umer Shafique Muhammad Salman 《Arabian Journal of Chemistry》2010,3(4):219-224
Complexes of enaminones; 4-N,N-diethylamine-pent-3-ene-2-one [HL1], 4-N,N-di n-propylamine-pent-3-ene-2-one [HL2] and 4-N,N-dicyclohexylamine-pent-3-ene-2-one [HL3] with Fe(II) and Zn(II) ions were prepared by reacting the equimolar ethanolic solutions of the ligands (HL1, HL2 and HL3) with ethanolic metal solutions. The complexes formed, were characterized by infrared, ultraviolet and atomic absorption spectroscopy. Ligands and their metal complexes were tested against Escherichia coli and Staphylococcus aureus bacteria to assess their antibacterial action using disc diffusion method. Ligands were completely inactive against bacteria whereas the complex Zn (HL1) has significant action on both bacteria, indicating that it has a good potential as bactericide. Other complexes have normal antiseptic character. 相似文献
107.
This paper addresses an identical parallel machine scheduling problem with job release dates and unavailability periods to
minimize total weighted completion time. This problem is known to be NP-hard in the strong sense. We propose a new lower bound
that can be computed in polynomial time. The test on more than 8 400 randomly generated instances shows a very significant
improvement with respect to existing results for previously studied special cases: without unavailability constraints, unweighted
version, or identical job release dates. For instance, the average improvement for the unweighted problem is as much as 20.43%
for 2 machines, 53.03% for 7 machines and 66.70% for 15 machines. For some instances, the improvement can be even as much
as 93%. 相似文献
108.
Callystatin A, a polyketide marine natural product, has been known since 1997 after its isolation from the sponge Callyspongia truncata by Kobayashi et al. It belongs to the leptomcyin family of natural products with a highly conjugated and stereodefined skeleton. The challenging structural topographies and remarkable anti-proliferative properties of (?)-Callystatin A stimulated many researchers to pursue the total synthesis of this marine polyketide. This review is exclusively focused on the research undertaken towards the concise, asymmetric total synthesis of Callystatin A over the last two decades. The various target oriented synthetic pathways are discussed in a chronological order to give a comprehensive overview. 相似文献
109.
A new mechanism bypass in a wall-bounded internal flow is proposed and the proposal is checked by direct numerical simulations
of high temporal and spatial resolution. The mechanism is based on the interactions of the localized perturbations, rather
than the effect of a single perturbation investigated so far in the classical bypass transition process. It is first shown
by theoretical considerations that two pairs of quasistreamwise vortices can interact near the wall in such a manner that
the compression (stretching) of the existing wall-normal vorticity induced by one of the pairs can enhance a new streamwise
vorticity zone that can lead to new coherent structures and enhance considerably the transition process. Direct numerical
simulations confirm this hypothesis. 相似文献
110.
Advanced analytical techniques for the extraction and characterization of plant‐derived essential oils by gas chromatography with mass spectrometry 下载免费PDF全文
In recent years, essential oils have received a growing interest because of the positive health effects of their novel characteristics such as antibacterial, antifungal, and antioxidant activities. For the extraction of plant‐derived essential oils, there is the need of advanced analytical techniques and innovative methodologies. An exhaustive study of hydrodistillation, supercritical fluid extraction, ultrasound‐ and microwave‐assisted extraction, solid‐phase microextraction, pressurized liquid extraction, pressurized hot water extraction, liquid–liquid extraction, liquid‐phase microextraction, matrix solid‐phase dispersion, and gas chromatography (one‐ and two‐dimensional) hyphenated with mass spectrometry for the extraction through various plant species and analysis of essential oils has been provided in this review. Essential oils are composed of mainly terpenes and terpenoids with low‐molecular‐weight aromatic and aliphatic constituents that are particularly important for public health. 相似文献