ZnO-decorated SiC@C hybrids with strong electromagnetic absorption.

A novel strategy is provided to improve the absorption of SiC nanomaterials through surface carbonization of SiC nanowires and hydrolysis. SiC@C-ZnO composites were synthesized with different dosages of ZnNO3·6H2O. Composition, microstructure, and electromagnetic properties of the composites were characterized and analyzed. Results from TEM and XRD show that crystalline ZnO particles adhere to the surface of amorphous carbon, and the ZnO content increases as a function of a dosage of ZnNO3·6H2O. The as-prepared SiC@C-ZnO hybrids exhibit effective electromagnetic absorption, which is related to a synergy effect of different dielectric loss processes. The minimum reflection loss reached -65.4 dB at 11 GHz at a sample thickness of 3.1 mm, while the effective absorption bandwidth (EAB) reached 7 GHz at a sample thickness of 2.56 mm. Furthermore, the EAB of the samples can also cover the whole X band and Ku band at small sample thicknesses (2.09-3.47 mm). The excellent properties of the materials suggest great prospect as electromagnetic absorbers.

Omni-functional crystal: Advanced methods to characterize the composition and homogeneity of lithium niobate melts and crystals.

Lithium niobate (LN) is a type of multifunctional dielectric and ferroelectric crystal that is widely used in acoustic, optical, and optoelectronic devices. The performance of pure and doped LN strongly depends on various factors, including its composition, microstructure, defects, domain, and homogeneity. The structure and composition homogeneity can affect both the chemical and physical properties of LN crystals, including their density, Curie temperature, refractive index, and piezoelectric and mechanical properties. In terms of practical demands, both the composition and microstructure characterizations these crystals must range from the nanometer scale up to the millimeter and wafer scales. Therefore, LN crystals require different characterization technologies when verifying their quality for various device applications. Optical, electrical, and acoustic technologies have been developed, including x-ray diffraction, Raman spectroscopy, electron microscopy, and interferometry. To obtain detailed structural information, advanced sub-nanometer technologies are required. For general industrial demands, fast and non-destructive technologies are preferable. This review outlines the advanced methods used to characterize both the composition and homogeneity of LN melts and crystals from the micro- to wafer scale.

Controllable Fabrication of SiC@C-Fe3O4 Hybrids and Their Excellent Electromagnetic Absorption Properties.

In this work, a batch of novel ternary hybrids (SiC@C-Fe3O4), characterized by SiC nanowires core, carbon shell, and adhered Fe3O4 nanoparticles were controllably synthesized via surface carbonization of SiCnw followed by hydrothermal reaction. Carbon, which was derived from SiC with nanometer thickness, possesses an amorphous structure, while Fe3O4 nanoparticles are in a crystalline state. Simultaneously, the inducement of Fe3O4 nanoparticles can provide significant magnetic loss, which is well-tuned by changing the molar content of iron precursors (FeCl3·6H2O and FeCl2·4H2O). SiC@C-Fe3O4 hybrids show great electromagnetic absorption performance owing to the synergy effect of dielectric and magnetic losses. The minimum refection loss can reach to -63.71 dB at 11.20 GHz with a thickness of 3.10 mm, while the broad effective absorption bandwidth (EAB) can reach to 7.48 GHz in range of 10.52-18.00 GHz with a thickness of 2.63 mm. Moreover, the EAB can also cover the whole X band and Ku band. The outstanding performance of the obtained material implys that it is a promising candidate as an electromagnetic absorber.

[Determination of higenamine in Chinese herbal medicine, condiments, and topical medicine by QuEChERS combined with liquid chromatography-tandem mass spectrometry].

A method combining QuEChERS with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of higenamine in Chinese herbal medicine, condiments, and topical medicine. The sample was subjected to extraction using a formic acid-ethanol mixture, followed by purification of the QuEChERS sorbents; then, the extraction solution was introduced into the LC-MS/MS system for detection in multiple reaction monitoring (MRM) mode. Under the optimal conditions, the detection limit of the developed method was 0.03 ng/g, and the linear range was 0.10-100 ng/g with a relative standard deviation (RSD) of 4.33% (0.5 ng/g, n=7). The method was then applied to the determination of higenamine in 13 kinds of Chinese herbal medicine, four kinds of condiments, and a topical medicine. Higenamine was detected in dried lotus leaf, dried lotus seed, Chinese yam, Yuzhu, Yam, Sichuan pepper, Cassia, and the topical medicine at 9667.6, 1183.8, 21.5, 8.2, 8.5, 148.6, 21.3, and 173.3 µg/kg, respectively. The recoveries of higenamine in Sichuan pepper and cassia was 92.6%-109.8%. In conclusion, the method is fast, simple, reliable, and suitable for use in batch operation.

Genetic variation of world soybean maturity date and geographic distribution of maturity groups.

The maturity date of soybean (Glycine max (L.) Merr.) is sensitive to photoperiod, which varies with latitude and growing seasons. The maturity group (MG) system, composed of 13 MGs, is a major approach in characterizing varieties' ecological properties and adaptable areas. A total of 512 world soybean varieties, including 48 MG checks, were tested at a major site (Nanjing, 32.04°N) with portions tested in supplementary sites (Heihe, 50.22°N; Mudanjiang, 44.60°N; Jining, 35.38°N and Nanning, 22.84°N) in China to explore the world-wide MG distribution. The maturity date of the world soybean varied greatly (75-201 d) in Nanjing. Along with soybeans disseminated to new areas, the MGs further expanded during the last 70 years from MG I-VII to the early MG 0-000 in the north continents and to the late MG VIII-X in the south continents with the growth period structure differentiated into two subgroups in each MG 0-VIII except V. The cluster analysis among MGs and subgroups using genome-wide markers validated the MG sequential emergence order and the subgroup differentiation in eight MGs. For future evaluation, in addition to one major site (Nanjing), one supplementary southern site (Nanning) and one supplementary northern site (Heihe) are sufficient.

An induction heating device using planar coil with high amplitude alternating magnetic fields for magnetic hyperthermia.

BACKGROUND: Induction heating devices using the induction coil and magnetic nanoparticles (MNPs) are the way that the magnetic hyperthermia is heading. OBJECTIVE: To facilitate the induction heating of in vivo magnetic nanoparticles in hyperthermia experiments on large animals. METHODS: An induction heating device using a planar coil was designed with a magnetic field frequency of 328 kHz. The coil's magnetic field distribution and the device's induction heating performance on different concentrations of magnetic nanoparticles were measured. RESULTS: The alternating magnetic field produced in the axis position 165 mm away from the coil center is 40 Gs in amplitude; magnetic nanoparticles with a concentration higher than 80 mg. mL-1 can be heated up rapidly. CONCLUSION: Our results demonstrate that the device can be applied not only to in vitro and in small animal experiments of magnetic hyperthermia using MNPs, but also in large animal experiments.

[Apoptosis of HL-60 cells induced by crystal proteins from Bacillus thuringiensis Bt9875].

OBJECTIVE: To study the effect of Bt9875 crystal protein treated with proteinase K on human cancer cells, HL-60. METHODS: We used the methods of Thiazolyl Blue Tetrazolium Bromide, fluorescence microscopy examination, agarose gel electrophores and flow cytometry to detect the growth inhibition rate and apoptosis characters of the HL-60 cells that were treated with different concentration of Bt9875 crystal protein. RESULTS: Bt9875 crystal protein inhibited the growth of HL-60 cells evidently in a dose-dependent manner, with minimal effects on normal human peripheral blood mononuclear cells (PBMCs). The nuclei of HL-60 cells showed the characteristics of apoptosis. The analysis by flow cytometry indicated that the apoptosis rate of HL-60 cells was 52% after treatment with Bt9875 crystal protein (100 microg/mL). DNA analyzed by agarose gel electrophoresis showed "ladder" pattern. CONCLUSION: Bt9875 crystal protein could inhibit the growth of HL-60 and induced its apoptosis, which provided a foundation for use of Bt9875 crystal protein to cure the acute myeloid leukemia.

Red American ginseng: ginsenoside constituents and antiproliferative activities of heat-processed Panax quinquefolius roots.

Red Asian ginseng ( Panax ginseng C. A. Meyer, Araliaceae) is used in many Oriental countries. In this study, the saponin constituents and anticancer activities of steamed American ginseng ( Panax quinquefolius L.) roots were evaluated. The contents of 12 ginsenosides in the roots were determined using high performance liquid chromatography (HPLC). After the steaming treatment (100 - 120 degrees C for 1 h and 120 degrees C for 0.5 - 4 h), the quantity of 7 ginsenosides decreased and that of 5 others increased. The content of ginsenoside Rg3, a previously recognized anticancer compound, increased significantly when the root was steamed at 120 degrees C for 0.5 - 3 h. The antiproliferative effects of unsteamed and steamed (120 degrees C for 1 h and 2 h) American ginseng root extracts were assayed by the modified trichrome stain (MTS) method using three cancer cell lines (SW-480, HT-29, NSCLC). Heat-processing increased the antiproliferative effect of American ginseng significantly, and the activity of the extract from roots steamed for 2 h was greater than that of roots steamed for 1 h. Chemical constituents and antiproliferative activities of white and red Asian ginseng have also been evaluated. Five representative ginsenosides, Rb1, Rd, Re, Rg2 and Rg3, were studied. Ginsenoside Rg3 had the most potent effect. The antiproliferative activities of red American ginseng are augmented when ginsenoside Rg3 is increased.

Determination of major ginsenosides in Panax quinquefolius (American ginseng) using high-performance liquid chromatography.

In order to determine the active ingredients in root extracts of Panax quinquefolius (American ginseng), a gradient HPLC method involving UV photodiode array detection was applied to separate and quantify simultaneously the ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf and Rg1. All ginseng saponins were baseline-resolved under the selected conditions, and the detection limits were 1.0 microg/mL or less. The method has been applied to analyse ginsenosides extracted from American ginseng cultivated in both Wisconsin and Illinois. Ginsenosides Re and Rb1 were the two main ginseng saponins in the root. The amounts of Re in 5- and 7-year Illinois-cultivated samples were greater than those found in ginseng cultivated for 3 or 4 years in Wisconsin, whereas the levels of Rb1 were greater in the younger Wisconsin samples.

[Fractal structure of Abies fabri, dominant tree species in dark coniferous forest at the upper reach of Yangtze River].

Based on the theory of fractal geometry, branching patterns of primitive Abies fabri in the dark coniferous forest ecosystem at the upper reach of Yangtze River were studied. The results showed that the maximum crown width was appeared at inferior 20% of the crown height, and its volume could be simulated by the combination of a round table and a cone. The surface of the crown and their branching patterns of Abies fabri had the common typical fractal characters, the fractal dimensions (FD) were 2.3232 and 1.8119, and the correlation coefficient was 0.99.

[Plot analysis in the dark coniferous ecosystem using GPS and GIS techniques].

It is generally difficult to survey in primary forests located on high-altitude region. However, it is convenient to identify and to recognize plots accompanied by GPS and GIS techniques, which can also display the spatial pattern of arbors precisely. Using the method of rapid-static positioning cooperated with tape-measure, it is concluded that except some points, the positioning was relatively precise, the average value of RMS was 2.84, variance was 2.96, and delta B, delta L, and delta H were 1.2, 1.2, and 4.3 m with their variances being +/- 0.6, +/- 1.1, and +/- 21.1, respectively, which could meet the needs of forestry management sufficiently. Accompanied by some other models, many ecological processes under small and even medium scale, such as the dynamics of gap succession, could also be simulated visually by GIS. Therefore, the techniques of "2S" were patent for forest ecosystem management under the fine scale, especially in the area of high altitude.