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71.
Journal of Computer Virology and Hacking Techniques - With macOS increasing popularity, the number, and variety of macOS malware are rising as well. Yet, very few tools exist for dynamic analysis...  相似文献   
72.
Telecommunication Systems - We study the physical-layer security of multi-hop secondary network under spectrum sharing constraint caused by the primary, which consists of many simultaneously...  相似文献   
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74.
The styrene–EPDM–vinylacetate (SEV) graft polymer, which linked respectively the styrene (St) unit and vinylacetate the (VAc) unit to the ethylene–propylene–diene terpolymer (EPDM) backbone was synthesized by two‐step graft polymerizations: First the graft polymerization of VAc onto EPDM was carried out, and then St was added successively in the prepolymerized solution and further polymerized for a given period to obtain SEV. The effects of concentration of EPDM and an initiator, mole ratio of VAc to St, polymerization time, temperature, and solvent were examined on the graft polymerizations. The synthesized graft polymers (SEVs) that have different contents of St or VAc were identified by Fourier transform IR spectrum. The highest graft ratio has been obtained by 10 wt % of EPDM, 1.0 mole ratio of VAc to St, and 1.0 wt % of BPO in toluene for 48 h at 70°C. The glass transition temperature of SEV is lower than that of poly(vinyl acetate) (PVAc) and polystyrene (PS). The thermal stability of SEV is higher than that of PVAc, PS, and the acrylonitrile–butadiene–styrene (ABS) resin. The tensile strength of SEV was improved as compared with that of EPDM. The light resistance and weatherability of SEV were better than those of ABS. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2296–2304, 2000  相似文献   
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Summary Vinylidene cyanide has been copolymerized in solution by radical reaction with equal initial mole fraction of para substituted acetoxystyrenes. The copolymers have been characterized by means of DSC, TGA and GPC. These products are stable up to 220° and have no visible glass transition temperature. The microstructure of these new copolymers has been studied by 13CNMR; they have an alternating structure and monomers units are arranged in head-to-tail placements.  相似文献   
77.
FA and tocopherol composition of Vietnamese oilseeds   总被引:1,自引:0,他引:1  
Seeds of 40 oilseed species from 23 different plant families (Brassicaceae, Cucurbitaceae, Fabaceae, Sapindaceae, Malvaceae, Gnetaceae, Clusiaceae, Bruseraceae, Ranunculaceae, Convolvulaceae, Amaranthaceae, Tiliaceae, Basellaceae, Solanaceae, Umbelliferae, Labiatae, Compositae, Theaceae, Euphorbiaceae, Caesalpiniaceae, Sapotaceae, Anacardiaceae, and Connaraceae) grown in Vietnam were analyzed for oilseed oil content, FA, and vitamin E. The seed oil content varied between 0.2 g/100 g for Mangifera indica and 75.7 g/100 g for Calophyllum inophyllum, whereas only nine seeds contained more than 40% oil. The tocopherol content ranged from 26 (Sapindus mukorossi) to 9361 mg/kg (Litchi chinensis). In nine seed oils unusual FA such as conjugated, cyclopropenoic, or epoxy FA were found.  相似文献   
78.
Topics in Catalysis - CO2 reforming of methanol for producing hydrogen was experimentally carried out in a fixed-bed reactor on 10%Ni/SiO2. The 10%Ni/SiO2 was completely reduced during H2...  相似文献   
79.
N-formylation is a common pre- and post-translational modification of the N-terminus or the lysine side chain of peptides and proteins that plays a role in the initiation of immune responses, gene expression, or epigenetics. Despite its high biological relevance, protocols for the chemical N-formylation of synthetic peptides are scarce. The few available methods are elaborate in their execution and the yields are highly sequence-dependent. We present a rapid, easy-to-use one-pot procedure that runs at room temperature and can be used to formylate protected peptides at both the N-terminus and the lysine side chain on the resin in near-quantitative yields. Only insensitive, storage-stable standard chemicals – formic acid, acetic anhydride, pyridine and DMF – are used. Formylation works for both short and long peptides of up to 34 amino acids and over the spectrum of canonical amino acids.  相似文献   
80.
Two series of macrocyclic plasmin inhibitors with a C-terminal benzylamine group were synthesized. The substitution of the N-terminal phenylsulfonyl group of a previously described inhibitor provided two analogues with sub-nanomolar inhibition constants. Both compounds possess a high selectivity against all other tested trypsin-like serine proteases. Furthermore, a new approach was used to selectively introduce asymmetric linker segments. Two of these compounds inhibit plasmin with Ki values close to 2 nM. For the first time, four crystal structures of these macrocyclic inhibitors could be determined in complex with a Ser195Ala microplasmin mutant. The macrocyclic core segment of the inhibitors binds to the open active site of plasmin without any steric hindrance. This binding mode is incompatible with other trypsin-like serine proteases containing a sterically demanding 99-hairpin loop. The crystal structures obtained experimentally explain the excellent selectivity of this inhibitor type as previously hypothesized.  相似文献   
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