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We report a direct C-H aminoalkylation reaction using two light-activated H-atom transfer catalyst systems that enable the introduction of protected amines to native adamantane scaffolds with C-C bond formation. The scope of adamantane and imine reaction partners is broad and deprotection provides versatile amine and amino acid building blocks. Using readily available chiral imines, the enantioselective synthesis of the saxagliptin core and rimantadine derivatives is also described.

An N-heterocyclic carbene (NHC)-catalyzed strategy has been developed to address the issue of using toxic transitional metals in the field of C-C bond activation. The novel reaction mode enables an efficient docking between the cyanoalkyl from the cycloketone oxime derivative and the acyl group from the aldehyde, affording ketonitrile in moderate to good yields, which is one kind of useful building block for synthesizing nitrogen-containing pharmacophores.

A new general de novo synthesis of pharmaceutically important α-aryl β-perfluoroalkyl ketones has been disclosed. Compared with trifluoromethylation-initiated radical 1,2-aryl migration of α,α-diaryl allylic alcohols, this protocol employs a new strategy of biomimetic carbene catalysis to assemble alkene, aldehyde and perfluoroalkyl reagents, providing access to products with excellent flexibility of the aryl unit and perfluoroalkyl group. This method also demonstrates excellent functional group compatibility, including some Grignard reagent sensitive groups.

A nickel-catalyzed 1,2-aminoarylation of oxime-ester-tethered alkenes with boronic acids was developed. A variety of pyrroline derivatives were synthesized in good yields via the successive formation of C(sp3)–N and C(sp3)–C(sp2) bonds. For cyclobutanone-derived oxime esters, the reaction provided aliphatic nitriles incorporating an aromatic group in the γ-position. A mechanism involving iminyl radical and carbon-centered radical intermediates was proposed.

There are a large number of independent matrix and vector operations in the lattice-based homomorphic encryption. These operations are suitable for GPU, which can greatly improve the efficiency of homomorphic operations. In this paper, we analyze the structure of the homomorphic encryption algorithm and verify the reliability of the homomorphic encryption software library, debug and analyze the fully homomorphic encryption software library TFHE and its corresponding GPU version cuFHE, and then compare their efficiency. The experimental results show that the GPU version TFHE is 4.5 times faster than the CPU version TFHE, so the GPU can greatly improve the homomorphic running speed of the homomorphic encryption scheme.

Aiming at the problem that the amount of calculation of correlation energy analysis is too large in the process of attacking multiple S-box corresponding keys, this paper proposes a multiple S-box correlation energy analysis model based on particle swarm optimization. The particle swarm optimization algorithm has the characteristics of simple structure, fast search speed and memory, therefore, our model simultaneously attacks multiple S-boxes, which can reduce the amount of calculation, thereby achieving the goal of recovering the key efficiently and correctly. Finally, experimental analysis and verification results of the DES algorithm indicate that our new energy analysis model has about 55% improvement in efficiency and 30% improvement in accuracy over traditional energy analysis models.

A new method for the direct functionalization of diamondoids has been developed using photoredox and H-atom transfer catalysis. This C–H alkylation reaction has excellent chemoselectivity for the strong 3º C–H bonds of adamantanes in polyfunctional molecules. In substrate competition reactions, a reversal in selectivity is observed for the new H-atom transfer catalyst reported here when compared to six known photochemical systems. Derivatization of a broad scope of diamondoids and adamantane-containing drugs highlights the versatility and functional group tolerance of this C–H functionalization strategy.

A novel amine-catalyzed nucleophilic trifluoromethylthiolation between Morita–Baylis–Hillman carbonates and O-octadecyl-S-trifluorothiolcarbonate has been developed. The regioselectivity of this reaction can be controlled by choosing different solvents, affording primary allylic SCF3 products in THF and secondary allylic SCF3 products in CHCl3 as major products. The mechanistic investigation indicated that DABCO plays a dual role in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates.

A redox-economical strategy for the synthesis of trifluoromethylated enamides using copper catalysis is reported. The reaction employs the inexpensive Langlois reagent (CF3SO2Na) and takes place without the need of an external oxidant. The trifluoromethylated enamide products can easily be converted into the corresponding ketone, saturated amide or oxazole.

Hydroquinine anthraquinone-1,4-diyl diether [(DHQ)(2)AQN]-catalyzed unprecedented asymmetric domino annulation reactions of acylidenoxindoles/isatins, acylidenoxindoles and allenoates are disclosed in this communication, providing a facile access to hexahydrofuro[2,3-b]furans containing four contiguous chiral centers in good to excellent yields along with good to excellent ee values and moderate to good dr values. Based on theoretical investigations, a concerted [3+2] ring-closure process was proposed, in which steric hindrance and pi-pi stacking interaction between catalyst and substrate subtly co-control the diastereoselectivity of the reaction.

Mesoporous titanium dioxide/graphitic carbon microspheres were synthesized by a simple nanocasting route using monodisperse silicon dioxide microspheres as the template. The characterize and the morphology of the titanium dioxide/graphitic carbon microspheres have been analyzed by means of XRD, N2-sorption, SEM, TEM, TG-DTA and EDAX. Indicated by the experimental results and the theoretical analysis, the anatase titanium dioxide nanoparticles of 8-14 nm in diameter were highly dispersed in the graphitic carbon microspheres. The obtained material can be used as catalyst or battery material. Key words: titanium dioxide/graphitic carbon; Microspheres; Nanocasting route;Mesoporous

An iron-catalyzed coupling reaction of O-acyloximes and O-benzoyl amidoximes with silyl enol ethers is reported. The protocol provides access to functionalized pyrroles, 1,6-ketonitriles, pyrrolines and imidazolines via carbon-centered radicals generated from an initially formed iminyl radical. The intramolecular cyclization and ring-opening processes of the iminyl radical take place preferentially over reactions that proceed through a 1,3-hydrogen transfer, providing insights into iron-catalyzed reactions with oxime derivatives. The cheap and environmentally friendly iron catalyst, the broad substrate scope and the functional group compatibility make this protocol useful for synthesis of valuable nitrogen-containing products.

The reaction of isoquinoline and allenoate with activated ketone resulted in a novel three component reaction, affording [1,3]oxazino[2,3-a]isoquinoline derivatives in moderate yields along with moderate diastereoselectivities via 1,4-dipolar cycloaddition. It was also found that when isatins were used as substrates, the regioselectivity of cycloadducts was different from those using ethyl trifluoropyruvate as substrate.

An interesting DBU-mediated intramolecular isomerization of arylmethylenecyclopropenes 1 to alkylidenecyclopropanes (ACPs) has been described in this context. A variety of ACPs were obtained through a base-assisted manner in moderate to good yields under mild conditions with good stereoselectivities in most cases.

One-pot thermal-induced [3+2] cycloaddition/silica gel-promoted fragmentation sequence between isatin ketonitrones and electron-deficient alkynes affords spiro[indoline]oxindoles in moderate to excellent yields along with good diastereoselectivities. The detailed mechanism of silica gel-promoted fragmentation has been clarified by experiment and DFT calculations.

Breviflavone B is a novel chiral phytoestrogen that mimics the biological functions of 17β-estradiol (E2), an estrogen which is naturally produced in our body. It has exhibited a much higher estrogen receptor (ER) bioactivity than E2 or other phytoestrogens. Breviflavone B specifically activates ER at a low dose without activating other steroid receptors, and inhibits estrogen-stimulated breast cancer cell proliferation at high doses, making it a potential treatment option for breast cancer patients. In this report, a new liquid chromatography aprroach has been developed to isolate Breviflavone B from Epimedium Brevicornum herbal extracts. After passing through DIAION HP20 resin, the ethanolic extract of Epimedium Brevicornum was firstly fractionalized by a Diol column, then further separated by a C18 column using preparative HPLC, and finally purified by an ODS-MCR-HPS column in HPLC under gradient mode. In each stage of separation, the ER bioactivities of the each fraction were measured by estrogen receptor-driven reporter gene bioassays to guide the chromatographic fractionations. The results showed that the new combination of Diol and C18 and ODS-MCR-HPS column chromatography provided better separation selectivity than our previously-reported C18 column chromatography for isolation of Breviflavon B from Epemidium herbs. Pure Breviflavon B was successfully isolated from the ethanolic extract of Epimedium Brevicornum herb via this new approach of chromatographic fractionations guided by the bioassays.

Integrated multilayer wrapped vessel is a new type of multilayer high pressure vessel construction diffusely used in various process industrial productions. The prestress of the integrated multilayer wrapped vessel of inside diameter 500mm during its manufactural process was investigated. The experimental results showed that, the circumferential prestress distributions in the inner cylinder and the laminate during its manufactural process were approximately exponential function, thus in order to make the circumferential prestress contribution in the inner cylinder even as possible, the laminates should be staggered uniformly as the same circumferential angle during the manufactural process of the actual vessel, which is of an important significance to insure its manufactural quality and safe application.

Energy efficiency is the primary consideration of the design of error control protocol of WSN and energy efficiency analysis is the key point of the present related literature research. However, while emphasizes are on the theoretical analysis and experiments are simulated by advanced programming language such as Matlab、C++ and so on, definitions of some restrictive or operation systems on hardware side of sensor nodes in practical usage are neglected, which lead to the inaccurate conclusion of the error control energy efficiency analysis. In this paper, samples of package-loss and error package and distribution of error codes in error packages are obtained through experiment statistics of a large amount of entity nodes and energy efficiency analysis and comparison of Error Control Techniques of WSN are conducted based on error characteristics.

In this paper, a novel and efficient steganalysis based on improved K-means clustering using One-Class Support Vector Machine (OC-SVM) was proposed to blindly determine the existence of hidden messages in an image. The performance of sample clustering is concerned in the OC-SVM with multi-sphere. In previous work, the K-means was mainly used to create such multi-sphere by clustering. But the traditional K-means depends on initial clustering centers and ended local minimum value. So, to improve the clustering performance of K-means, the SA is employed into the scheme, which can create more reasonable multi-sphere by finding global optimum solutions in the clustering process. Simulation results with the chosen feature set and well-known steganographic techniques indicated that our approach was able to afford reasonable accuracy to distinguish between covers and stego images.

A robust watermarking scheme that used computer-generated holograms as the watermark is in NSCT (NonSampled Contourlet Transform) domain was proposed. To maintain imperceptibility and robustness, a repeated embedding algorithm is adopted to embed the mark hologram into the low-frequency subband of the NSCT host image. Compared with other watermark schemes using digital holograms, the proposed algorithm has the obvious advantage in robustness The experimental results demonstrated that the proposed method had good robustness to resist common attacks such as, rotation, scaling, translation, image flipping, combined attacks, filtering, occlusion, cropping, and JPEG compression.

Aiming at the character of high bit error rate and energy constraints on WSN, this paper proposed an adaptive error control scheme based on link quality indicator(LQI). The PHY specification of IEEE802.15.4 provided accurate measurement of channel quality for WSN, according to the quantitative relationship between LQI and bit error rate, this paper divided the channel quality into eight levels non-uniformly, furthermore, eight different BCH code were chosen correspondingly. The motes choose optimal BCH code as its error correction scheme in real time. Experimental results show the scheme is high in energy efficiency, meanwhile, drops the error probability effectively.

Biological treatment played an important role in the treatment of landfill leachate. In the current study, acid mine drainage (AMD) was used as a source of sulfate to strengthen the anaerobic treatment of landfill leachate. Effects of chemical oxygen demand (COD) and SO42- mass concentration ratio on the decomposition of organic matter, methane production and sulfate reduction were investigated and the microbial community was analyzed using the high throughout methods. Results showed that high removal efficiency of COD, methane production and heavy metal removal was achieved when the initial COD/SO42- ratio (based on mass) was set at 3.0. The relative abundance of anaerobic hydrogen-producing bacteria (Candidatus Cloacamonas) in the experimental group with the addition of AMD was significantly increased compared to the control. Abundance of hydrogenotrophic methanogens of Methanosarcina and Methanomassiliicoccus was increased. Results confirmed that AMD could be used as sulfate resource to strengthen the biological treatment of landfill leachate.

A novel intramolecular oxycyanation of methylenecyclopropanes is reported that proceeds through oxidative cleavage of the N-CN bond and subsequent palladium transfer from N to O of the amide group. A range of substituted benzo[d][1,3]oxazines with a cyano group are readily furnished by this newly developed oxycyanation reaction. Tris(4-trifluoromethylphenyl)phosphine as a ligand has been found to be crucial to effectively promote the transformation with high chemo- and regioselectivity. Moreover, the reaction outcome can be significantly affected by the electronic effect of the acyl group attached to the nitrogen atom of methylenecyclopropanes. When R(3) is a chloromethyl group, the pyrrolo[2,3-b]quinoline derivative is obtained by thermal-induced [3+2] cycloaddition of methylenecyclopropane to the methanediimine intermediate.

(La0.7Sr0.3)MnO3 (LSMO) thin films were prepared on Si (100) substrate by pulsed laser deposition (PLD). Both structure and surface morphology of the films were investigated by X-ray diffraction (XRD) and atomic force microscopy (AFM). Furthermore, the chemical states and chemical composition of the films were determined by X-ray photoelectron spectroscopy (XPS) near the surface. The results indicate that the films grown on Si (100) substrates have a single pseudo cubic perovskite phase structure with a high (100) orientation. The XPS results show that La, Sr and Mn exist mainly in the forms of perovskite structure and a SrO layer was found on outermost surface.

Heat energy storage characteristics of a new type of PCM heat exchange tube was researched, in which it took the traditional double-tube exchanger as the total construction foundation and phase change material(CaCl2•6H2O) was filled in the annular area between the inner tube and the outer tube. As air with different temperatures flowed through the PCM heat exchange tube, temperature measurements were carried out at the inlet and the outlet by the experimental system. The experimental results showed that, a new type of PCM heat exchange tube could store heat energy from the hot air by the phase change material in the annular area, and discharge the stored heat energy into the required fluid if necessary. Thus it has two functions of heat exchange and heat energy storage, and is mainly suitable for recovery and utilizations of heat energy in greenhouses, buildings, air conditioning and manifold industrial afterheat or waste heat.

A core-shell structure material, carbon fiber/ZnO was prepared by a surface modification precipitation process in aqueous solution. The structure, absorptive properties and photoluminescence properties of the composites were investigated. Results showed that the energy bandgap of samples calculated from the absorptive spectra was about 3.30eV. The green emission peak of the samples was ascribed to the oxygen vacancies.

Treatment of pyridine and dimethyl acetylenedicarboxylate derivatives with N-substituted isatylidene derivatives resulted in three-component condensations, affording 1′,9a′-dihydrospiro[indoline-3,2-quinolizin]-2-one derivatives in high yields and with good diastereoselectivities through 1,4-dipolar cycloadditions.

A core-shell structure material, carbon fiber/MoS2was prepared by a surface modification precipitation process in aqueous solution. A nucleation model for this structure was proposed. Coating was obtained from 10-4M ammonium molybdate. The energy band gap of MoS2calculated from the absorption spectra was about 1.97eV. CFs/MoS2core-shell structure has strong absorption in the wavelength range from 400 to 1000nm, which is well fitted to visible light of the solar spectrum. The result of thermal analysis indicates that the composite is stable below 403 °C.

A novel intramolecular oxycyanation of methylenecyclopropanes is reported that proceeds through oxidative cleavage of the N-CN bond and subsequent palladium transfer from N to O of the amide group. A range of substituted benzo[d][1,3]oxazines with a cyano group are readily furnished by this newly developed oxycyanation reaction. Tris(4-trifluoromethylphenyl)phosphine as a ligand has been found to be crucial to effectively promote the transformation with high chemo- and regioselectivity. Moreover, the reaction outcome can be significantly affected by the electronic effect of the acyl group attached to the nitrogen atom of methylenecyclopropanes. When R(3) is a chloromethyl group, the pyrrolo[2,3-b]quinoline derivative is obtained by thermal-induced [3+2] cycloaddition of methylenecyclopropane to the methanediimine intermediate.

A novel amine-catalyzed nucleophilic trifluoromethylthiolation between Morita–Baylis–Hillman carbonates and O-octadecyl-S-trifluorothiolcarbonate has been developed. The regioselectivity of this reaction can be controlled by choosing different solvents, affording primary allylic SCF3 products in THF and secondary allylic SCF3 products in CHCl3 as major products. The mechanistic investigation indicated that DABCO plays a dual role in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates.

Integrated multilayer wrapped pressure vessel is widely used in process industrial production. In allusion to its manufactural process and structural characteristics as well as considering the frictional force between the laminates in the relative displacement of the laminates, the calculation formulae in the laminate or the inner cylinder prestressed by the wrapping force of the hydraulic manipulator were derived by principles of mechanics. The investigative results of the prestress distribution in the integrated multilayer wrapped vessel structure have a certain direct significance for its actual manufacture and insuring its manufactural quality.

Since phase change energy storage exchanger has two functions of heat exchange and heat energy storage, it is an important component of heat energy storage technique with phase change materials, its research has been thought highly by people, and great achievements have been obtained during the recent years. A review on its various structures and their research and development was made in this paper, and its further research and applications were also analyzed and forecasted.

Highly ordered nanotube arrays were fabricated via electrochemical anodization of Ti-6Al-4V (TC4) alloy foils in aqueous fluorine containing electrolytes. The formation of ordered nanotubular films was affected by the applied anodization potential and the anodization time. The optimal applied voltage and anodization time were 20V and 1h, respectively, as-prepared anodic nanotubular films were in highly ordered with the average inner diameter of about 120nm, the wall thickness of 17nm and the tube length about 300nm. The tubular nanostructures were examined by field emission scanning electron microscopy. The possible nanotube formation mechanism was also discussed.

Nanotubular films on the surface of Ti-2Al-1.5Mn (TC1) alloy were fabricated by electrochemical anodization technique in aqueous ammonium fluoride solutions at 20V for 3h. The photoelectrochemical activities of the nanotube arrays were investigated, as well as their phase, structure, composition and photoabsorption properties. The photo-absorption in the visible region and the photoelectrochemical response were improved obviously. It is attributed to the Mn ion doping of TiO2 lattices. Furthermore, the resulted nanotube arrays are expected to have bright application prospects for solar utilization.

Self-organized nanotube arrays were prepared by a facile two-electrode electrochemical anodization on pure Ti in a 0.5wt% NH4F aqueous electrolyte. The surface morphology, structure, optical and photoelectrochemical behaviors of the nanotubular films were considered. The as-formed nanotubes are highly ordered with ~700nm in length and the average tube diameter is about 90nm. By annealing the initially amorphous films at different temperatures, the importance of the crystalline nature is confirmed. The photoelectrochemical properties are investigated and the highest photocurrent of 2.297 mA/cm2 is obtained under AM1.5 100 mW/cm2 illumination at 0.6 V (vs Ag/AgCl).

Novel amine-catalyzed tunable cycloadditions between allenoates and dithioesters, providing a divergent synthesis of 2,3-dihydro-1,4-oxathiines and enantioenriched thietanes is reported.

The title reaction affords a series of fully functionalized pyrrole derivatives (III) and (V) via rhodium azavinyl carbene intermediates.

Hydroquinine anthraquinone-1,4-diyl diether [(DHQ)(2)AQN]-catalyzed unprecedented asymmetric domino annulation reactions of acylidenoxindoles/isatins, acylidenoxindoles and allenoates are disclosed in this communication, providing a facile access to hexahydrofuro[2,3-b]furans containing four contiguous chiral centers in good to excellent yields along with good to excellent ee values and moderate to good dr values. Based on theoretical investigations, a concerted [3+2] ring-closure process was proposed, in which steric hindrance and pi-pi stacking interaction between catalyst and substrate subtly co-control the diastereoselectivity of the reaction.

The chemoselective [4+2] vs. [2+2] cycloaddition between allenoates and dithioesters can be controlled by switching the nucleophilic amine catalyst. The two modes of cyclizations represent the first example of controllable and chemoselective annulations between allenoates and dienophiles catalyzed by amine. These cyclizations are useful in offering a divergent synthesis of sulfur-containing heterocycles. On the basis of this investigation, it can be realized that dithioesters with a vicinal electron-withdrawing group can react not only like a Michael acceptor but also as a ketone or imine.

Rh(II)-catalyzed intermolecular [3+2] cycloaddition of 2 H-azirines with N-sulfonyl-1,2,3-triazoles is disclosed, in which a series of fully functionalized pyrroles is produced via rhodium azavinyl carbene intermediates. A distinct feature of this reaction is that the azavinyl carbene serves as a [2 C] equivalent, instead of as [1 C] or aza-[3 C] synthons, which have been reported previously in cyclopropanations and [3+n] cycloadditions. Moreover, this methodology has also been successfully applied in the total synthesis of URB447 as well as the formal synthesis of Atorvastatin (Lipitor).

The first example for the preparation of enantioenriched azo compounds from hydrazones and Morita–Baylis–Hillman adducts has been developed, affording azo compounds incorporating an oxindole scaffold in up to 91% yield along with a 93% ee value under the catalysis of (DHQ)2AQN.

This novel three component reaction gives an easy access to isoquinoline derivatives via a 1,4-dipolar cycloaddition reaction.

Nanocrystalline particles of Cu–Zn alloy in the size range from 10 to 140 nm with a mean particle size of 85 nm have been prepared from α-Cu–Zn alloy wire containing 39.8 at.% Zn by a wire electrical explosion method by adopting appropriate process parameters. The particles are identified as a mixture of α, β, γ, and e phases of Cu–Zn alloy from X-ray powder diffraction (XRD). Most of the powders are hexagonal in shape, with only a small part being spherical and cubic. The particle size of the product obeys the log-normal distribution law, which indicates that the formation of particles with different sizes corresponds with probability dynamics. A possible mechanism for the formation of the alloy nanoparticles is proposed.

A novel Au(I)-catalyzed 6-endo-dig cyclization of 1,1-bis(indolyl)-5-alkynes (I) and (III) is developed to give bis(indole) alkaloid analogues through a pseudo 1,5-migration of an indole moiety.

One-pot thermal-induced [3+2] cycloaddition/silica gel-promoted fragmentation sequence between isatin ketonitrones and electron-deficient alkynes affords spiro[indoline]oxindoles in moderate to excellent yields along with good diastereoselectivities. The detailed mechanism of silica gel-promoted fragmentation has been clarified by experiment and DFT calculations.