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In the present work, the effects of phase constitution on the magnetic and mechanical properties of FeCoNi(CuAl)x (x = 0–1.2, in molar ratios) high-entropy alloys (HEAs) have been investigated by using vibrating sample magnetometer (VSM), mechanical tester combined with X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and differential scanning calorimeter (DSC). From the experimental results, the crystallographic structures of FeCoNi(CuAl)x HEAs transform from single face-centered cubic (FCC) phase for 0 ≤ x ≤ 0.6 to body-centered cubic (BCC) phase combined with minor FCC phase for 0.9 ≤ x ≤ 1.2, whereas FCC plus BCC duplex phases are found in the range of 0.7 ≤ x

In this paper, the magnetocaloric properties of Gd1&minus, xTbx alloys were studied and the optimum composition was determined to be Gd0.73Tb0.27. On the basis of Gd0.73Tb0.27, the influence of different Fe-doping content was discussed and the effect of heat treatment was also investigated. The adiabatic temperature change (&Delta, Tad) obtained by the direct measurement method (under a low magnetic field of 1.2 T) and specific heat capacity calculation method (indirect measurement) was used to characterize the magnetocaloric properties of Gd1&minus, xTbx (x = 0~0.4) and (Gd0.73Tb0.27)1&minus, yFey (y = 0~0.15), and the isothermal magnetic entropy (&Delta, SM) was also used as a reference parameter for evaluating the magnetocaloric properties of samples together with &Delta, Tad. In Gd1&minus, xTbx alloys, the Curie temperature (Tc) decreased from 293 K (x = 0) to 257 K (x = 0.4) with increasing Tb content, and the Gd0.73Tb0.27 alloy obtained the best adiabatic temperature change, which was ~3.5 K in a magnetic field up to 1.2 T (Tc = 276 K). When the doping content of Fe increased from y = 0 to y = 0.15, the Tc of (Gd0.73Tb0.27)1&minus, yFey (y = 0~0.15) alloys increased significantly from 276 K (y = 0) to 281 K (y = 0.15), and a good magnetocaloric effect was maintained. The annealing of alloys (Gd0.73Tb0.27)1&minus, yFey (y = 0~0.15) at 1073 K for 10 h resulted in an average increase of 0.3 K in the maximum adiabatic temperature change and a slight increase in Tc. This study is of great significance for the study of magnetic refrigeration materials with adjustable Curie temperature in a low magnetic field.

Magnetic field annealing is an important method to enhance the magnetic properties of amorphous alloys. In this work, the effects of magnetic field annealing intensity on the magnetic properties, mechanical properties, and microstructure of Fe80Si9B11 amorphous ribbons were investigated. It can be seen from the results that the magnetic induction at 1600 A/m (B1600), maximum permeability (μm), coercivity (Hc), Elastic modulus (Er), and Hardness were improved with an increase of the magnetic field intensity. When the magnetic annealing intensity was 2.5 × 10−4 T, the B1600, μm, Hc, Er and Hardness of the sample were improved by 9%, 298%, 67%, 23% and 3%, respectively, compared with those of the as-spun sample. TEM results showed that there are some spherical symmetric clusters present in the 653 K × 2.5 × 10−4 T sample. This may be an important reason for the improvement of the magnetic properties. Compared with the 653 K × 1 T sample, the magnetic field intensity of the 653 K × 2.5 × 10−4 T sample was only 0.025%. However, the values of B1600, μm, Hc, Er and Hardness of the latter reached 96%, 82%, 115%, 90% and 94% of the former, respectively. It means that during the magnetic field annealing process, applying only a small magnetic field can obviously enhance the magnetic and mechanical properties of Fe80Si9B11 amorphous alloy. This provides a theoretical basis for the further improvement of the magnetic and mechanical properties of Fe80Si9B11 alloys, and in the energy saving. The reasons for the changes of magnetic and mechanical properties caused by different magnetic field intensities are discussed.

The characteristic magnetic domains at the surfaces of melt-spun La–Fe–Si ribbons under different thermal processing conditions are explored using room-temperature Lorentz force microscopy and electron holography. In as-quenched ribbons, the magnetic domain structure is found to change from a tree-like morphology on the surface far from the copper wheel during quenching to a vortex-type domain structure on the surface in contact with the wheel. In the initial stages of annealing, domains on both surfaces developed a vortex behavior. Detailed microstructural observations demonstrated nanocrystalline α -(Fe,Si) regions embedded in the majority La(Fe,Si) 13 phase due to a partially completed peritectoid reaction between α -(Fe,Si) and LaFeSi. The room temperature magnetic domains disappeared along with the residual α -(Fe,Si) upon extended heat treatment, yielding a homogeneous La(Fe,Si) 13 material. Magnetometry measurements and analysis reveal the absence of strong coupling between the α -(Fe,Si) and La(Fe,Si) 13 phases, so that the presence of α -(Fe,Si) nanocrystallites with a vortex-type structure does not favor an enhanced magnetocaloric response in the ribbons.

The structure and magnetocaloric properties of La-Ce-Fe-Si alloys have been studied. The samples were prepared by melt spinning, the surface speed of the Cu wheel being 55 m/s. The as-spun ribbons were subsequently annealed at 1273 K for different times (10 min−1 h) and then quenched to room temperature. When the annealing time was 20 min, on a 1.5-T applied magnetic field, the maximum magnetic entropy change (ΔS M) of the ribbons reached values of 33.8 J/kg K at the Curie temperature of T C ∼ 182 K. When the annealing time was longer than 20 min, the maximum magnetic entropy change (|ΔS M,Max|) tended to decrease while the T C remained almost unchanged. In the annealing process, La/Ce located at grain boundaries was easily oxidized on the ribbon surface. The presence of large grain sizes and La2O3 or LaO were shown to degrade the magnetocaloric properties. On the other hand, the substitution of Ce for La improved the magnetocaloric effect of La-Fe-Si compounds, which is of practical importance for magnetic refrigeration.

We undertook a novel batch production approach for the synthesis of CeO2 nanopowders doped with rare earth elements. Solid solution nanopowders of Ce1−x La x O2−δ (x = 0.15) were successfully synthesized in a large-scale and low-cost production by hydrolyzing and oxidizing Ce-La-C alloys at room temperature and subsequent calcining of their powders at different temperatures (873–1073 K) for 1 h. The Ce-La-C alloys were prepared in a vacuum induction melting furnace. The final products were characterized by x-ray diffraction, transmission electron microscopy, Brunner–Emmet–Teller (BET) surface area analyzer, and Raman spectroscopy. The calculated lattice parameters of the cubic fluorite-type phase of CeO2 tended to increase when La3+ was incorporated into CeO2. The F 2g band shift and the absence of a peak corresponding to La2O3 in the Raman spectra consistently confirmed the incorporation of the La3+ ion into CeO2, and the formation of Ce1−x La x O2−δ solid solutions as manifested by increased oxygen vacancy defects. High-quality Ce1−x La x O2−δ nanopowders of ~10–15 nm diameter with a high BET surface area of ~77 m2 g−1 were obtained. The average crystallite size of Ce1−x La x O2−δ was found to be smaller than that of CeO2 for the same calcination temperature of 1073 K, demonstrating that the introduction of La3+ into CeO2 can stabilize the host lattice and refine the grain size at high temperatures.

The corrosion behavior of 2205 duplex stainless steel (DSS) was investigated in the hot concentrated seawater under vacuum pressures by using electrochemical measurement techniques. The vacuum pressure results in the decrease of dissolved oxygen concentration and even boiling of solution. 2205 DSS passivates spontaneously under various vacuum pressures. The vacuum pressures (no lower than 28.4 kPa) greatly influence the polarization resistance, passive film composition and oxygen reduction reaction. The pressure reduction and the violent boiling of solution distinctly decrease the pitting potential, but increase the repassivation potential. They may enhance both the occurrence and repassivation tendencies of stable pitting corrosion.

In this paper, the effects of different melt spinning speeds on the mechanical properties of (TiZr)0.5(Ni0.6Cr0.1V0.1)2.1 amorphous ribbons were studied. Tensile tests of the specimens were used to investigate mechanical behavior and mechanical properties of amorphous ribbons. The effects of cooling rate on the glass transition temperature of amorphous ribbons was discussed. The correlation between the microstructure of serrated flow behavior in stress-strain curves and melt spinning speeds of ribbons was also evaluated. In addition, when the spinning speed was 45 m/s, a large number of dense and uniform dimples appeared on the fractured surface of the specimens. Furthermore, characteristics of serrated flow behavior were obvious, which meant that Ti-Zr-Ni-Cr-V amorphous ribbons showed minor plastic behavior. It is assumed that the influence of free volume led to a serrated flow behavior of the amorphous materials, and made the amorphous material exhibit partially plastic properties. Increasing the strain rate sensitivity meant the free volume increased with the increasing spinning speed. Tensile strength (&sigma, b) and elongation (&delta, ) of samples exhibited a dramatic increasing trend with an increase in the spinning speed. In particular, Ti-Zr-Ni-Cr-V amorphous ribbons showed better mechanical properties, namely the tensile strength of the amorphous ribbon samples significantly increased from 321 MPa at a spinning speed of 30 m/s to 675 MPa at a speed of 45 m/s. The elongation increased from 0.53% at a speed of 30 m/s to 1.29% at a speed of 45 m/s.

In this study, ferrocenedicarboxylic acid (FDA) has been introduced between an ITO electrode and ZnO interlayer to improve the performance of inverted polymer solar cells. The highest power conversion efficiency (PCE) of 9.06% is achieved among the measurements. Besides, the average PCE of FDA/ZnO based devices is observed with 11.9% enhancement (8.73% vs. 7.80%) compared to ZnO-only devices. Electrical characterization, surface morphology, wetting properties, as well as exciton generation rate and dissociation probability were investigated to understand the impact of FDA insertion on the interfacial properties. It was found that exciton dissociation efficiency and charge collection efficiency were significantly improved after inserting FDA, while the surface morphology, average roughness and water contact angle of the ZnO film were not changed. It was thought that FDA connected to the ITO electrode and ZnO film because of its carboxyl groups, which lead to a compact interfacial contact and reduced charge recombination. In addition, the devices based on the FDA/ZnO interlayers displayed improved stability in the argon-filled glove box without any encapsulation for about 1000 h compared to the ZnO-only devices. This study provides a new idea to introduce materials with functional groups between ITO/metal oxides interfaces to achieve more efficient charge collection and device performance.

The promise of the La–Fe–Si alloys for energy efficient magnetic refrigeration devices stems from a strong magneto-structural transition in the La(Fe,Si) 13 (1:13) phase near room temperature. The formation of the 1:13 phase during rapid solidification was compared in detailed microstructural studies of the wheel-side and free-side surfaces of melt-spun ribbons. On the free-side, clusters of similarly-oriented crystallites are observed; chemical segregation of La, Fe, and Si leads to a nanoscale texturing of α-Fe and LaFeSi. In contrast, equiaxed 1:13 grains ∼100–400 nm form the microstructure of the wheel-side surface, with a minor α-Fe phase precipitated in the matrix. Upon annealing, the 1:13 phase grows via dissolution of the α-Fe phase on the wheel side and a peritectoid reaction from the free side. For longer annealing times, the completion of the peritectoid reaction improves the magnetic entropy change under a magnetic field change of 1.5 T from 12 J/kg K (2 min) to 17 J/kg K (2 h), and increases the Curie temperature of the ribbons from 189 K to 201 K.

Dithiocarbamates (DTCs) exhibit a broad spectrum of antitumor activities, however, their molecular mechanisms of antitumor have not yet been elucidated. Previously, we have synthesized a series of novel dithiocarbamate derivatives. These DTCs were examined for cytotoxic activities against five human cancer cell lines. In this study, one of dithiocarbamate (DTC1) with higher potential for HeLa cells was chosen to investigate molecular mechanisms for its anti-tumor activities. DTC1 could inhibit proliferation, and highly induce apoptosis in HeLa cells by activating caspase-3, -6 and -9; moreover, activities of caspase-3, -6 and -9 were inhibited by pan-caspase inhibitor, Z-VAD-FMK. Furthermore, DTC1 decreased the levels of Bcl-2 and Bcl-xL, and increased expression of cytosol cytochrome c, Bak, Bax and p53 in a time-dependent manner but had no effect on the level of Rb. It was shown that DTC1 induced HeLa cells apoptosis through a p53-dependent pathway as tested by the wild type p53 inhibitor, pifithrin-α. Additionally, the relative expression of E6 and E7 were evaluated in HPV18-positive (HeLa cells) by real-time PCR and western blotting. The results firstly demonstrated that DTC1 suppressed both expression of E6 mRNA and E6 oncoprotein, but had no effect on the expression of E7 mRNA and protein in HPV18. Our results suggested that DTC1 may serve as novel chemotherapeutic agents in the treatment of cervical cancer and potential anti-HPV virus candidates that merit further studies.

Nonlinear optical materials are essential for the development of solid-state lasers. KBe

Birefringent materials are of great importance in optical communication and the laser industry, as they can modulate the polarization of light. Limited by their transparency range, few birefringent materials, except α-BaB2O4 (α-BBO), can be practically used in the deep ultraviolet (UV) region. However, α-BBO suffers from a phase transition and does not have enough transparency in the deep UV region. By introducing the relatively small alkali metal Na+ cation and the F– anion to keep the favorable structural features of α-BBO, we report a new birefringent crystal Na3Ba2(B3O6)2F (NBBF), which has the desirable optical properties. NBBF not only maintains the large birefringence (Δn = no – ne = 0.2554–0.0750 from 175 nm to 3.35 μm) and extends its UV cutoff edge to 175 nm (14 nm shorter than α-BBO) but also eliminates the phase transition and has the lowest growth temperature (820 °C) among birefringent materials. These results demonstrate that NBBF is an attractive candidate for the next generation of deep U...

Pd(II) complexes with imidazole linked to dithiocarbamate derivatives were synthesized by reacting 1-(alkyldithiocarbonyl)-imidazoles with PdCl2 in a 2 : 1 molar ratio. The complexes were characterized by elemental analyses, FT-IR, and 1H NMR. The single crystal structure of 4 shows that the ligand is chelated by nitrogens in imidazole, instead of sulfur, to palladium. All synthesized compounds were tested for in vitro anticancer activities. Compound 5 had better activities in the HL-60 cell line and twofold better activities in the HeLa cell line than that of cisplatin.

The generation of intense coherent deep-UV light from nonlinear optical materials is crucial to applications ranging from semiconductor photolithography and laser micromachining to photochemical synthesis. However, few materials with large second harmonic generation (SHG) and a short UV-cutoff edge are effective down to 200 nm. A notable exception is KBe2BO3F2, which is obtained from a solid-state reaction of highly toxic beryllium oxide powders. We designed and synthesized a benign polar material, Ba4B11O20F, that satisfies these requirements and exhibits the largest SHG response in known borates containing neither lone-pair-active anions nor second-order Jahn-Teller-active transition metals. We developed a microscopic model to explain the enhancement, which is unexpected on the basis of conventional anionic group theory arguments. Crystal engineering of atomic displacements along the polar axis, which are difficult to attribute to or identify within unique anionic moieties, and greater cation polarizabilities are critical to the design of next-generation SHG materials.

The Mn-doped CeO 2 nanopowders with high catalysis activity were successfully fabricated through a simple hydrolyzed-oxidized approach. Firstly, the alloy Ce 37 Mn 18 C 45 was prepared in vacuum induction melting furnace. Subsequently, Mn-doped CeO 2 nanopowders with 142 m 2 /g of specific surface area were obtained through a simple hydrolyzed-oxidized procedure of the alloy. Those nanopowders were heat treated at different temperatures. The obtained materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and energy dispersive spectroscopy (EDS). And the catalytic activity on vinyl chloride (VC) emission combustion was investigated. The results showed that those nanopowders after hydrolyzed-oxidized from Ce 37 Mn 18 C 45 mainly consisted of CeO 2 and Mn 3 O 4 . Manganese element increased the thermal stability of CeO 2 nanopowders. The Mn-doped CeO 2 nanopowders had three morphologies. Small particles were Mn-doped CeO 2 , square particles were Mn 3 O 4 and the rods were Mn 3 O 4 and Mn 2 O 3 . The Mn-doped CeO 2 nanopowders had good vinyl chloride (VC) emission catalytic performance.

Three new borates containing nonmetal compounds, [C(4)H(12)N][BO(4)(C(7)H4(O))(2)] (1), [C(8)H(20)N][BO(4)(C(7)H(4)O)2] (2) and [C(6)H(18)N(2)](0.5)[BO(4)(C(7)H(4)O)(2)] (3) have been prepared, aiming at the formation of extended supramolecular networks with organic-inorganic hybrid materials of salicylic acid and boric acid. The corresponding compounds have been characterized by chemical and spectroscopic techniques. X-ray diffraction analyses of available single crystals revealed that the molecular structures of the three compounds have the same isolated [BO(4)(C(7)H(4)O)(2)] anion. The [BO(4)(C(7)H(4)O)(2)] anion with a distorted BO(4) tetrahedron is formed by bidentate coordination of the B atom to two salicylic acid molecules via the O atoms of the central carboxyl and alpha-hydroxyl groups. The three compounds display violet luminescence with emission maxima around 365 nm.

Optimizing of alloy composition and heat-treatment for rapidly solidified Ce–Fe–B magnets can lead nanocrystalline products with enhanced magnetic properties. In this work, the magnetic properties and domain structures of the nanocrystalline Ce[Formula: see text]Fe[Formula: see text]Co1Zr[Formula: see text]B6 have been investigated. The results show that hard Ce2Fe[Formula: see text]B magnetic phase and paramagnetic CeFe2 phase are crystallized for the heat treated alloys, while the volume fraction and grain size of Ce2Fe[Formula: see text]B and CeFe2 phases change significantly with the increase of annealing temperature. The enhanced coercivity H[Formula: see text] of 6.32 kOe and maximum energy products (BH)[Formula: see text] of 5.52 MGOe have been observed for the Ce[Formula: see text]Fe[Formula: see text]Co1Zr[Formula: see text]B6 ribbons at the optimal annealing temperature of 520[Formula: see text]C and 580[Formula: see text]C, respectively. Meanwhile, the magnetization reversal behaviors and the nucleation field of the annealed sample were discussed in detail. The domain structures analysis provides more information on the characteristic of the domain width W as well as the exchange interactions.

In this study, both solvent evaporation and hydrothermal methods were employed to grow hydrated sodium borate crystals using NaOH and H3BO3 as reagents, and transparent and colorless single-crystals were successfully obtained with sizes up to 12 × 6 × 6 mm3 and 6 × 5 × 4 mm3, respectively. The structure is determined by single-crystal X-ray diffraction techniques. The title compound crystallizes in the trigonal space group R32, with a = 11.1042(16) A, b = 11.1042(16) A, c = 21.131(4) A, Z = 9 and R1 = 0.0322, wR2 = 0.0840. Infrared and transmission spectra are presented for the reported material. The powder second-harmonic generation (SHG) intensity measured by the Kurtz-Perry method indicates that the SHG effect of Na2B4O12H10 is about one-third times that of KH2PO4 (KDP).

Colorless and transparent Na3VO2B6O11 (NVB) crystal has been grown by the top seeded solution growth method using NaVO3 as the flux at cooling rates of 0.8-1.5 degrees C/day, in the temperature range 610-650 degrees C. A well-developed morphology of the crystals was observed and analyzed. The grown crystals were characterized by powder X-ray diffraction (PXRD), infrared spectroscopy and second harmonic generation (SHG) test. (C) 2010 Published by Elsevier B.V.

A new nonlinear optical crystal, Na3VO2B6O11, hit s been grown by the top-seeded sol Lit ion growl h method using it Na2CO3V2O5 flux. The structure of the compound was determined by single-crystal X-ray diffraction. It crystallizes in the noncentrosymmetric orthorhombic system, space group P2(1)2(1)2(1), with cell parameters a = 7.7359(9) angstrom, h = 10. 1884(12) angstrom, c = 12.5697(15) angstrom, V = 990.7(2) angstrom(3), and Z = 4. Na3VO2B6O11 has, a three-dimensional structure consisting of hexaborate groups connected by VO4 tetrahedra with the sodium atoms distributed in channels through Out the three-dimensional network. The refractive indices have been measured by the minimum deviation technique and fit to the Sellmeier equations. Nonlinearoptical Measurements on the compound demonstrate that the material has second harmonic generation properties, with an efficiency approximately the same as that of KH2BO4.

Sizable single crystals of a nonlinear optical (NLO) material, Bi2ZnOB2O6, were grown by the Kyropoulos method from stoichiometric ratio compound melt. It is a congruent melting compound and crystallizes in the orthorhombic system, space group Pba2. The morphologies and habits of Bi2ZnOB2O6 crystals grown using [100], [010], and [001] seeds were studied. The SHG efficiency of Bi2ZnOB2O6 is 3−4 times that of KDP (KH2PO4). Its birefringence is pretty large (0.085−0.106). The experiments prove that Bi2ZnOB2O6 crystal is nonhygroscopic and excellently deliquescence resistant.

A single crystal of Bi2ZnOB2O6 has been grown with sizes up to 18 x 13 x 6 mm(3) by the top-seeded growth method for the First time with high quality. It crystallizes in the orthorhombic system, space group Pba2 with unit-cell parameters a = 10.8200(7) angstrom, b = 11.00 14(7) angstrom, c = 4.8896(3) angstrom, Z = 4, V = 582.03(6) angstrom(3). Bi2ZnOB2O6 has a three-dimensional network consisting of ZnB2O76- layers alternating with six-coordinated Bi3+ cations along the c axis. Transmission spectrum of Bi2ZnOB2O6 crystal was reported. The refractive indices of the crystal were measured by the minimum deviation technique and fitted to the Sellmeier equations. The powder second-harmonic generation (SHG) properties measured by the Kurtz-Perry method indicate that Bi2ZnOB2O6 is phasematchable.

Nanocomposite alloys with the compositions of Nd 8.5 Fe 77.6− x Co 5 Zr 2.7 Ga x B 6.2 ( x = 0, 0.3, 0.6, 0.8, 1.0) were prepared by melt spinning. It was found that a small amount of 0.6 at.% Ga addition is beneficial to improve the hard magnetic properties of the alloy. The melt-spun Nd 8.5 Fe 77 Co 5 Zr 2.7 Ga 0.6 B 6.2 ribbons were annealed in a pulsed magnetic field. The results revealed that the remanence J r and the maximum energy product ( BH ) max were obviously improved when annealed below the Curie temperature of the alloy. The best magnetic properties of J r = 0.975 T, i H c = 582 kA/m, and ( BH ) max = 131 kJ/m 3 were obtained for the ribbons annealed at 300 °C in a pulsed magnetic field. The ( BH ) max was enhanced by 23.8% compared with that of the ribbons without magnetic annealing. It provides a new way to improve the magnetic properties of permanent magnets produced by pulsed magnetic annealing at temperatures below the Curie point of the alloys.

The effects of Co and Zr additions on the microstructure, magnetic properties and crystallization behaviour of nanocomposite Nd 2 Fe 14 B/α-Fe magnets have been investigated. It was found that Co addition decreases the precipitation temperature of crystalline phases, improves the Curie temperature of magnetic phases and clearly increases the remanence. On further Zr addition, the crystallization behaviour changes from a two-step to a single-step process, and the grains are markedly refined, especially for the α-Fe phase. The unit cell and the Curie temperature of the Nd 2 Fe 14 B phase decrease, suggesting that Zr atoms partly enter the Nd 2 Fe 14 B structure and occupy the rare earth sites. Hence, the volume fraction of hard magnetic phase increases, the intrinsic coercivity increases from 445 kA/m for the Zr-free sample to 687 kA/m for the Zr-doped sample and a maximum energy product of 129 kJ/m 3 is achieved for Nd 9.5 Fe 76 Co 5 Zr 3 B 6.5 alloy.

High-quality single crystals of Pb17O8Cl18 with sizes of up to 7 mm x 2 mm x 2 mm are grown from a stoichiometric melt of PbO and PbCl2 (430 °C, 48 h) by a modified crystallization method in an open system.

Mid-IR nonlinear optical (NLO) materials are of great importance in modern laser frequency conversion technology and optical parametric oscillator processes. However, the commercially available IR NLO crystals (e.g., AgGaQ2 (Q = S, Se) and ZnGeP2) suffer from two obstacles, low laser damage thresholds (LDTs) and the difficulty of obtaining high-quality crystals, both of which seriously hinder their applications. The introduction of Cl, an element with a large electronegativity, and Pb, a relatively heavy element to promote the optical properties, affords an oxide-based IR NLO material, Pb17O8Cl18 (POC). High-quality POC single crystals with sizes of up to 7 mm × 2 mm × 2 mm have been grown in an open system. Additionally, POC exhibits a large LDT of 408 MW/cm(2), 12.8 times that of AgGaS2. POC also exhibits an excellent second harmonic generation response: 2 times that of AgGaS2, the benchmark IR NLO crystal at 2090 nm, and 4 times that of KDP, the standard UV NLO crystal at 1064 nm. Thus, we believe that POC is a promising IR NLO material.

Magnetic refrigeration based on themagnetocaloric effect (MCE) is a promising alternative to the conventional gas compression refrigeration, owing to its higher cooling efficiency, environmental friendliness, and compactness. The majority of research in this field is to seek materials that exhibit large MCE over a wide temperature range, with manufacturing flexibility, and are cost-effective. Among existing magnetocaloric materials, the cubic NaZn 13 -type La(Fe, Si) 13 alloys have attracted particular attention due to their giant MCE and cheap raw materials [1,2].

The nucleation mechanism involving rapid solidification of undercooled La-Fe-Si melts has been studied experimentally and theoretically. The classical nucleation theory-based simulations show a competitive nucleation process between the α-(Fe,Si) phase (size approximately 10 to 30 nm) and the cubic NaZn13-type phase (hereinafter 1:13 phase, size approximately 200 to 400 nm) during rapid solidification, and that the undercooled temperature change ∆T plays an important factor in this process. The simulated results about the nucleation rates of the α-(Fe,Si) and 1:13 phases in La-Fe-Si ribbons fabricated by a melt-spinner using a copper wheel with a surface speed of 35 m/s agree well with the XRD, SEM, and TEM studies of the phase structure and microstructure of the ribbons. Our study paves the way for designing novel La-Fe-Si materials for a wide range of technological applications.

A variety of 4-N atom substituted derivatives were synthesized and evaluated for their in vitro anticancer activities using 4-methylpiperazine-1-carbodithioic acid 3-cyano-3,3-diphenyl-propyl ester 4 as lead compound. Among them, compound 6a without any substituent on 4-N atom (R 1 = H) was found to be the most active anticancer agent with IC 50 = 5.3 μM against HL-60 and IC 50 = 11.5 μM against Bel-7402, respectively. Increase in the polarity and/or introduction of suitable acyl groups at the 4-N atom of the lead compound 4 are favorable for the improvement of activity.

The fragmentation patterns of a novel kind of dithiocarbamic acid esters with excellent anticancer activity were analyzed by positive ion electrospray ionization mass spectrometry in conjunction with tandem mass spectrometry (ESI/MS n ). The fragmentation patterns of sodium adduct ions [ M + Na] + were characterized with elimination of hydrogen cyanide and most of their counterparts could be observed. The fragmentation patterns of protonated molecular ions [ M + H] + were characterized with single bond cleavage between thiocarbonyl group and nitrogen atom, and between thiocarbonyl group and sulfur atom. The piperazine moiety of the molecular of [ M + H] + favors a rearrangement to expel azirane, and the suggested rearrangement mechanism is consistent with experimental observations.

Two-phase nanocrystalline ribbons were prepared by melt-spun and subsequent heat treatment. Excellent magnetic properties of the bonded magnet were achieved as follows: Br = 0.67 T, JHc = 664.3 kA·m-1, (BH) max = 75.0 kJ·m-3. The mean grain size of the ribbons heat-treated at 710 °C/ 4 min is about 50 nm. After heat-treated the ribbons at 750 °C/ 4 min, the mean grain size is about 100 nm.

1-(Alkyldithiocarhonyl)-imidazoles, 1-(methyldithio-carbonyl)-1,2,4-triazole and 1-(methyldithiocarhonyl)-benzotriazole were prepared in good to excellent yields from the reaction of imidazol, 1,2,4-1H-triazole and 1H-benzotriazole with carbon disulfide and corresponding alkylating agents in the presence of anhydrous potassium phosphate in acetone at room temperature within 2 hours.

Single crystals of the new UV nonlinear optical title material are prepared by solid state reaction of Cs2CO3, ZnO, H3BO3, and PbO in the molar ratio 1:1:5:1 (Pt crucible, 750 °C).

A sizeable single crystal of Bi2ZnOB2O6 (BZB) with dimensions of 65 x 35 x 30 mm(3) has been grown along the c-axis direction by the Czochralski method. Differential thermal analysis (DTA) results show that BZB melts congruently at 692 degrees C. The density and hardness of the BZB crystal have been measured, the measured density is in agreement with the calculated one and the Vickers hardness is 381-499 N/mm(2). (C) 2010 Published by Elsevier B.V.

Nonlinear optical (NLO) crystals are essential materials for generation of coherent UV light in solid state lasers. KBBF is the only material that can achieve coherent light below 200 nm by direct second harmonic generation (SHG). However, its strong layer habits and the high toxicity of the beryllium oxide powders required for synthesis limit its application. By substituting Be with Zn and connecting adjacent [Zn2BO3O2] ∞ layers by B3O6 groups, a new UV nonlinear optical material, Cs3Zn6B9O 21, was synthesized. It overcomes the processing limitations of KBBF and exhibits the largest SHG response in the KBBF family.

Low-cost La(FexSi1-x)13 alloys exhibiting the large magnetocaloric effect (MCE) are one of the most promising magnetic refrigerant candidates for room temperature magnetic refrigeration. The NaZn13-type phase (hereinafter 1:13 phase) is believed to play a key role in the MCE of these alloys. While the formation of the 1:13 phase directly from the melt upon cooling was challenging, in this paper we demonstrate that the 1:13 phase can be formed directly during solidification. We found that three kinds of solidification microstructure were formed because a competitive nucleation occurred between the 1:13 and α-(Fe,Si) phase during the solidification of LaFe11.5Si1.5 alloy. In case of a high cooling speed, a large amount of NaZn13–type phase with equiaxed grains and a small amount of α-(Fe,Si) phase were formed because of a dominant nucleation rate of 1:13 phase. When the cooling rate was small, a large number of α-(Fe,Si) phase with dendrites were formed because the nucleation rate of α-(Fe,Si) phase is larger than that of the 1:13 phase. These results revealed that nucleation rates of phases is very important to the composition formation and microstructure of LaFe11.5Si1.5 alloys.

Enterovirus 71 (EV71) is an etiology for a number of diseases in humans. Traditional Chinese herbs have been reported to be effective for treating EV71 infection. However, there is no report about the antiviral effects of CHA against EV71. In this study, plaque reduction assay demonstrated that the inhibitory concentration 50% (IC50) of CHA on EV71 replication is 6.3 µg/ml. When both CHA (20 µg/ml) and EV71 were added, or added post-infection at different time points, CHA was able to effectively inhibit EV71 replication between 0 and 10 h. In addition, CHA inhibited EV71 2A transcription and translation in EV71-infected RD cells, but did not affect VP1, 3C, and 3D expression. Furthermore, CHA inhibited secretions of IL-6, TNF-α, IFN-γ and MCP-1 in EV71-infected RD cells. Altogether, these results revealed that CHA may have antiviral properties for treating EV71 infection.

Ba4B11O20F is synthesized by solid state reaction of a stoichiometric mixture of Ba(NO3)2, H3BO3, and BaF2 (780 °C, 2 d).

The VPl gene of enterovirus 71 (EV71) was synthesized, construct a recombinant plasmid pET15b/VP1 and expressed in E. coli BL21. The recombinant VP1 protein could specifically react with EV71-infected patient sera without the cross-reaction with serum antibodies of coxsackievirus A16 (CA16), A4, A5, B3 and B5 as well as echovirus 6. In acute and convalescent phases, IgM and IgG antibodies of 182 serum samples were detected by ELISA with recombinant VP1 protein as a coated antigen. The results showed that the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of IgM antibodies in serum samples for the diagnosis of EV71 infection were 90.1, 98.4, 98.8 and 88.7%, respectively; similarly, those of IgG antibodies in serum samples were 82.4, 89.1, 91.5 and 78.1%, respectively. Five of 80 samples (6.25%) from CA16-infected patients were detected positive by ELISA with recombinant VP1 protein in which indicated the cross reactions and 0 of 5 samples from patients infected with other enteroviruses including CA4, CA5, CB3, CB5 and echovirus 6. Therefore, the recombinant VP1 protein of EV7l may provide a theoretical reference for establishing an effective antibody screening of IgM for EV71-infected patients with clinically suspected hand, foot, and mouth disease (HFMD).

Based on a novel lead compound 4-methylpiperazine-1-carbodithioic acid 3-cyano-3,3-diphenylpropyl ester 1, the systematic structural modification was carried out. All the synthesized compounds were evaluated for their in-vitro anticancer activities on four to six different cell lines at three different concentrations. Most of the tested compounds could selectively inhibit the growth of HL-60 and Bel-7402 cell lines at a medium concentration. Four compounds (3f, 3g, 3n, and 5) were selected for the IC(50) test, and the results revealed that three compounds (3g, 3n, and 5) showed almost the same or a slightly weaker activity than compound 1 against HL-60, and three compounds (3f, 3g, and 3n) showed > 2-fold higher potency than compound 1 against Bel-7402. The in-vivo efficacy of 3n center dot HCl was evaluated with transplanted hepatocyte carcinoma 22 as an in-vivo test model. It was found that 3n center dot HCl could inhibit significantly the growth of tumor, and that this effect was dose-dependent. Meanwhile, the compound 3n center dot HCl showed low toxicity compared with compound 1 center dot HCl as evidenced by the little body-weight loss. These results confirmed that compound 3n center dot HCl is more potent than the lead compound 1 center dot HCl. Preliminary structure-activity relationships indicated that: a) Both nitrile group and the cyclic amine containing at least two nitrogens were indispensable moieties to keep the activity; b) substitution of the piperazine ring is unfavorable for the improvement of activity; c) the suitable linker joining the piperazinyl dithiocarboxyl and diphenylacetonitril group should be ethylene; d) a non-coplanar arrangement of the two benzene rings appears to be essential for activity.

Transparent, good quality and fairly large-sized single crystals of the title compound are prepared from aqueous solutions of NaOH and H3BO3 by the standard evaporation method (45 °C, 3 weeks) and hydrothermally (autoclave, 180 °C, 2 d).

Based on a novel lead compound 4-methylpiperazine-1-carbodithioic acid 3-cyano-3,3-diphenylpropyl ester 1, the systematic structural modification was carried out. All the synthesized compounds were evaluated for their in-vitro anticancer activities on four to six different cell lines at three different concentrations. Most of the tested compounds could selectively inhibit the growth of HL-60 and Bel-7402 cell lines at a medium concentration. Four compounds (3f, 3g, 3n, and 5) were selected for the IC(50) test, and the results revealed that three compounds (3g, 3n, and 5) showed almost the same or a slightly weaker activity than compound 1 against HL-60, and three compounds (3f, 3g, and 3n) showed > 2-fold higher potency than compound 1 against Bel-7402. The in-vivo efficacy of 3n center dot HCl was evaluated with transplanted hepatocyte carcinoma 22 as an in-vivo test model. It was found that 3n center dot HCl could inhibit significantly the growth of tumor, and that this effect was dose-dependent. Meanwhile, the compound 3n center dot HCl showed low toxicity compared with compound 1 center dot HCl as evidenced by the little body-weight loss. These results confirmed that compound 3n center dot HCl is more potent than the lead compound 1 center dot HCl. Preliminary structure-activity relationships indicated that: a) Both nitrile group and the cyclic amine containing at least two nitrogens were indispensable moieties to keep the activity; b) substitution of the piperazine ring is unfavorable for the improvement of activity; c) the suitable linker joining the piperazinyl dithiocarboxyl and diphenylacetonitril group should be ethylene; d) a non-coplanar arrangement of the two benzene rings appears to be essential for activity.