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In this study, a series of (Ba 0.95 Ca 0.05 )(Ti 0.90 Sn 0.10 )O 3 – x LiF (BCTS– x LiF) (0≤ x ≤6 mol%) lead-free piezoceramics were fabricated by a conventional solid-state reaction method. The incorporation of LiF could significantly improve the sinterability of BCTS ceramics by reducing the sintering temperature from 1480 °C to 1250 °C, where a relative density over 90% was achieved with grown grains of 5–20 μm. X-ray diffraction and Raman spectroscopy experiments revealed that BCTS– x LiF ceramics are composed of coexisting R – O – T phases at 0≤ x ≤1 and R – T phases at 2≤ x ≤6 at room temperature. Optimal piezoelectric properties of d 33 =510 pC/N, k p =40.9%, ε r =5370, tan δ =0.019 and d S /d E =961 pm/V were obtained at x =5, which is attributed to the coexistence of R and T phases with an optimum ratio at room temperature and dense structure with large grains. [ABSTRACT FROM AUTHOR]

A Ser105Ala mutant of the lipase B from Candida antarctica enables 'perhydrolase-only' reactions. At the example of the chemoenzymatic Baeyer-Villiger oxidation of cyclohexanone, we demonstrate that with this mutant selective oxidation can be achieved in deep eutectic solvent while essentially eliminating the undesired hydrolysis reaction of the product. [ABSTRACT FROM AUTHOR]

A high piezoelectricity enhancement achieved in (Ba,Ca)(Ti,Sn)O 3 lead-free ceramics sintered with 4 mol% Li 2 O additives by intensifying effect of sintering temperature ( T S ) in a wide interval (1300–1450 °C) has been found to be related to both the point defects and phase structures. X-ray photoelectron spectroscopy confirmed a reduction of tetravalent cations in B-sites to lower valence state such as Ti 3+ and Sn 2+ along with an increased content as raising T S . Photoluminescence spectra indicated higher oxygen vacancy concentrations as T S is too low or too high than those at an intermediate T S range, which is attributed to the volatilization of Li + and the inadequate oxygen supply in environment at high T S . Owing to coexisting rhombohedral and tetragonal phases at room temperature, a high piezoelectric coefficient d 33 up to 578 pC/N was achieved as T S =1350 °C. [ABSTRACT FROM AUTHOR]

A series of Li2 CO3-added ( Ba0.95 Ca0.05)( Ti0.90 Sn0.10) O3 ( BCTS) ceramics were prepared by normal sintering at a low temperature of 1300°C; Their microstructure and electrical property evaluation were investigated with special emphases on the effect of Li2 CO3 addition. Adding Li2 CO3 significantly improves the sinterability of BCTS ceramics, resulting in a reduced sintering temperature by more than 150°C. The coexistence of R and T phases is confirmed by the Raman spectrum at room temperature for all samples and at a temperature range from −80°C to 40°C for sample with 3% mol Li2 CO3 addition. The specific ratio of R to T phase decreases with increasing temperature or Li2 CO3 addition. A higher εr is observed in T phase compared to R phase in the studied BCTS system. Better properties with d33 = 485 pC/N, kp = 39%, and Qm = 191 were obtained for BCTS sample with 3% mol Li2 CO3 addition, which is attributed to the increased grain size and density along with the variation in the specific ratio of R to T phase. [ABSTRACT FROM AUTHOR]

Orange juice is a kind of fruit juice with huge market share. The most common adulteration is the addition of mandarin juice and grapefruit juice. Therefore, it is necessary to develop a method that can simultaneously detect mandarin and grapefruit components in orange juice. In this study, the specific site of the trnL-trnF gene of mandarin and the specific site of the accD-psaI gene of grapefruit were used for digestion and capillary electrophoresis separation to establish a duplex PCR–RFLP–CE method of simultaneous detection of mandarin and grapefruit components. By this method, the detection limits of mandarin and grapefruit components were 5% and 2.5%, respectively. About the specificity, only the 83–177 bp amplified bands of mandarin and grapefruit were specifically digested, while none of them were cut in the 8 kinds of fruits such as pear, apple, peach, papaya, pineapple, hawthorn, grape and banana. Duplex PCR–RFLP–CE tests were performed on the 8 commercially available fruit juices. As a result, grapefruit components were found in orange juice (C5) and other ingredients to be identified in grapefruit juice (C8). The established duplex PCR–RFLP–CE method can provide an effective detection method for orange juice adulteration in the future. [ABSTRACT FROM AUTHOR]

The incorporation of unsaturated [Mn(1,2-dap)] 2+ , [Mn(1,2-dap) 2 ] 2+ , [Mn(2,2-bipy)] 2+ (1,2-dap=1,2-diaminopropane) complex cations with thioarsenate anions of [As III S 3 ] 3− and [As V S 4 ] 3 − led to three new hybrid manganese thioarsenates, namely, [Mn(1,2-dap)] 2 MnAs 2 S 6 ( 1 ), [Mn(1,2-dap) 2 ]{[Mn(1,2-dap)] 2 As 2 S 8 } ( 2 ) and (NH 4 )[Mn(2,2-bipy) 2 ]AsS 4 ( 3 ). In compound 1 , the unsaturated [Mn(1,2-dap)] 2+ complexes, [MnS 4 ] 6− tetrahedra and [As III S 3 ] 3− trigonal-pyramids are condensed to form the 1D [Mn(1,2-dap)] 2 MnAs 2 S 6 chain, whereas compound 2 features 2D layer composed of [Mn(1,2-dap)] 2+ and [Mn(1,2-dap) 2 ] 2+ complexes as well as [As V S 4 ] 3− tetrahedral units. For compound 3 , two [As V S 4 ] 3− anions bridge two [Mn(2,2-bipy)] 2+ complex cations into a butterfly like {[Mn(2,2-bipy)] 2 As 2 S 8 } 2 − anionic unit. Magnetic measurements indicate the ferrimagnetic behavior for compound 1 and antiferromagnetic (AF) behaviors for compounds 2–3 . The UV–vis diffuse-reflectance measurements and electronic structural calculations based on density functional theory (DFT) revealed the title compounds belong to semiconductors with band gaps of 2.63, 2.21, and 1.97 eV, respectively. The narrow band-gap of compound 3 led to the efficient and stable photocatalytic degradation activity over organic pollutant than N-doped P25 under visible light irradiation. [ABSTRACT FROM AUTHOR]

Background. Pigment epithelium-derived factor (PEDF) is demonstrated to be elevated in diabetes patients. However, no reports have emerged in pregnant women with gestational diabetes mellitus (GDM). This study was undertaken to investigate serum PEDF levels in GDM women and to evaluate PEDF as a biomarker to predict diabetes postpartum. Methods. Serum PEDF concentration and clinical characteristics were detected in the pregnant women with GDM (n = 120) and without GDM (control group, n = 120). Results. PEDF levels were elevated in subjects with GDM versus controls. Univariate correlations showed that serum PEDF levels were positively correlated with fasting glucose and fasting insulin levels, respectively, and negatively correlated with adiponectin. Receiver operating characteristic (ROC) analysis demonstrated that the AUC of serum PEDF for diabetes mellitus in women postpartum was 0.893. Conclusion. Serum PEDF was elevated in pregnant women with GDM, which is probably an early detection marker for predicting development of GDM to diabetes mellitus. [ABSTRACT FROM AUTHOR]

Abstract: The polymorphic phase transition (PPT) from tetragonal to orthorhombic symmetry was tailored in lead-free piezoelectric ceramics Li0.08(Na0.52+x K0.48)0.92NbO3 (LN0.52+x KN) by controlling excess Na content, which is opposite to the usually reported orthorhombic–tetragonal phase transition. The grain growth was accelerated by adding excess Na, resulting in an increased grain size from 2–3μm to 7–8μm and a bimodal grain size distribution for samples x=0.015–0.04. The optimized piezoelectric properties with, i.e. d 33=226pC/N and k p=36.8% were obtained in sample x=0.04 due to the PPT effect. The corresponding T C, P r, and E r were 468°C, 25.5μC/cm2 and 1.20kV/mm, respectively. [Copyright &y& Elsevier]

( Ba1− x Ca x)( Ti0.92 Sn0.08) O3 ( x = 0.00-0.06 mol) ceramics with a high relative density over 96% were prepared by a conventional sintering method at 1480°C. At room temperature, a polymorphic phase transition from orthorhombic phase to tetragonal phase was confirmed by the XRD patterns in the composition range of 0.04 ≤ x ≤ 0.06. A high piezoelectric coefficient d33 up to 568 pC/N was obtained at x = 0.05 mol, which is higher than the other component of ( Ba, Ca)( Ti, Sn) O3 system. At the same time, the corresponding planar electromechanical coupling factor kp, converse piezoelectric coefficient dS/ dE, and dielectric constant εr reach 47.7%, 1013 pm/V, and 23000, respectively. These results indicate that the ( Ba, Ca)( Ti, Sn) O3 ceramics are a promising candidate to replace for the lead-based piezoelectric materials. [ABSTRACT FROM AUTHOR]