This paper proposes a kinematic obstacle avoidance algorithm for Space hyper-redundant manipulators, and its basic idea is to use a static and a dynamic curve to constrain the macroshape of the manipulators simultaneously. The static curve is constructed based on a traditional rapidly exploring random tree algorithm, and a backbone curve is utilized as the dynamic curve. For these two curves, two novel shape control methods are proposed to accomplish the shape constraining process. Finally, we verify the reliability and effectiveness of our algorithm through simulations.

Nickel-coated carbon nanotubes (Ni-CNTs) were achieved by electroless plating. Laser cladded IN718 and IN718 with 10, 30, and 50 wt% additions of Ni-CNTs were fabricated. The structural evolution of CNTs in the laser-deposited layers was studied; the microstructure, tensile, and wear properties of the laser-cladded alloys were characterized. The results show that CNTs in the laser-deposited layers are mostly transformed to carbon nanoproducts (CNPs) in the forms of graphene nanosheets, graphene fragments, carbon nanoribbons, and diamond-like nanoparticles by unzipping, interbonding, collapsing, and curvature of CNTs. The interdendritic Laves phase formation is dramatically depressed due to the addition of Ni-CNTs, but the excess addition of the Ni-CNTs can undesirably increase the formation of NbC. The addition of Ni-CNTs effectively improves the tensile and wear properties. The most superior tensile and wear properties are achieved in the layers with 30 and 50 wt% additions of Ni-CNTs, respectively. The generation of intermetallic phase and CNPs are revealed to be two dominant effects both on the tensile and wear properties of the laser-cladded alloys.

Sources and implications of black carbon (BC) and mineral dust (MD) on two glaciers on the central Tibetan Plateau were estimated based on in situ measurements and modeling. The results indicated that BC and MD accounted for ~11 ± 1% and 4 ± 0% of the albedo reduction relative to clean snow, while the radiative forcing varied between 11 and 196 and 1–89 W m−2, respectively. Assessment of BC and MD contributions to the glacier melt can reach up 88 to 434 and 35 to 187 mm w.e., respectively, contributing ~9–23 and 4–10% of the total glacier melt. A footprint analysis indicated that BC and MD deposited on the glaciers originated mainly from the Middle East, Central Asia, North China and South Asia during the study period. Moreover, a potentially large fraction of BC may have originated from local and regional fossil fuel combustion. This study suggests that BC and MD will enhance glacier melt and provides a scientific basis for regional mitigation efforts.

In this contribution, we devoted ourselves to fabricating aggregation-induced emission (AIE) activity copolymers via one-pot combination of RAFT polymerization and Biginelli reaction for the first time. When the feeding ratio of TPB was 33.5%, the molar fraction of TPB was, respectively, about 14.2 and 22.5% in PEG-PTE1 copolymers by two-step strategy and PEG-PTE2 copolymers by one-pot strategy with the similar structure. The Mn of PEG-PTE1 increased to 59,300 from 52,800 of PEG-AE presoma with narrow PDI, which was more than Mn of PEG-PTE2 with 52,300. As compared with PEG-PTE2, when the feeding ratio of TPB was 48.6%, the molar fraction of TPB increased to 32.6% in PEG-PTE3. In aqueous solution, the as-obtained PEG-PTE2 copolymers can self-assemble into fluorescent organic nanoparticles (FONs) with 100–180 nm spherical morphology, the maximal emission peak of which presented at 460 nm with the obvious AIE phenomenon. Moreover, due to the low toxicity and excellent cell dyeing behavior, the as-prepared PEG-PTE2 copolymers displayed great potential for biomedical applications.

In this work, the nitrogen-doped carbon materials (NCM) and nitrogen/sulfur codoped carbon materials (NSCM) were prepared using conventional benzoxazine (BOZ) and sulfur-containing benzoxazine as precursor and SBA-15 as template. The morphology, structure, and electrochemical performance of carbon materials were characterized by scanning electron microscopy, transmission electron microscopy, the X-ray diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption–desorption, cyclic voltammetry, and galvanostatic charge–discharge. The results show that the as-prepared carbon materials have ordered mesoporous structure, large specific surface area, and excellent electrochemical properties. The NSCM treated at 800 °C exhibit an extremely high specific capacitance of 550 F/g at the current density of 0.5 A/g in 0.5 mol H2SO4 electrolyte, which shows great improvement compared with NCM. The nitrogen/sulfur codoping is suggested to be a very effective method to improve the performance of carbon materials, and the NSCM should be a promising candidate as electrode materials for supercapacitors.

In situ TiB2 particles with polyhedral or near-spherical morphology with more high-index crystal planes exposed were prepared by controlling the addition amount of Sc in commercial pure aluminum matrix. As the content of Sc increased, TiB2 morphology transformed from hexagonal platelets to polyhedral or near-spherical morphology with a decrease in particle size. In the present paper, a simple method to prepare near-spherical in situ TiB2 particles in Al matrix was explored and it was found that the reinforcement distribution was improved significantly. The different growth mechanism of TiB2 particles in Al and Al–Sc systems was discussed. The key reason for the morphology evolution was that the Sc was preferentially adsorbed on ${\bf \left\{ {1{\bf \overline{2}}12} \right\}}$, ${\bf \left\{ {11\overline{2}0} \right\}}$, and ${\bf \left\{ {10\overline{1}1} \right\}}$ which would inhibit the growth of these faces effectively and retain a lower-energy state of the polyhedral or quasispherical TiB2 particles in Al–Sc systems.

In this work, the negatively charged [NbMoO6]− nanosheets (NSs) were combined with positively charged [5,10,15,20-tetrakis (N-methylpyridinium-4-yl) porphyrinato cobalt] (CoTMPyP) to fabricate a sandwich-like CoTMPyP/[NbMoO6]− NSs intercalated material by a direct self-assembling process. The results confirmed that CoTMPyP cations formed an inclined monolayer between [NbMoO6]− NSs and the inclined angle was about 68°. The electrochemical properties of CoTMPyP/[NbMoO6]− NSs composite were also investigated by cyclic voltammetry and liner sweep voltammetry, which showed the enhanced electron transferred ability. The CoTMPyP/[NbMoO6]− NSs modified electrode displayed excellent electrocatalytic activity towards oxygen reduction with the reduction peak potential shifting from −0.681 to −0.235 V. And oxygen could be reduced to generate hydrogen peroxide with a two-electron process in neutral electrolytes. Moreover, the reduction peak current was linear relationship with the square root of scan rates, implying that the catalytic reaction depended on oxygen diffusion.

The 2Cr13/316L multilayered composite plates were fabricated by hot rolling with recycle heating step. The effect of rolling reductions on microstructure and properties was investigated. The 2Cr13 layer consists of martensite and lath ferrite, but the middle layer has less ferrite than both sides. The content and grains of ferrite increase with the increase of the reduction and number of reheating, which leads to a decrease in the hardness of the 2Cr13 layer. The hardness of the 2Cr13 layer is determined by the volume ratio of martensite and ferrite. Tensile strength of the specimens with the rolling reduction of 72% and 82% reached 815.8 MPa and 763.4 MPa, while elongations were 20% and 20.8%, respectively. With the increase of the rolling reduction, the fracture mode also changed from cleavage fracture to dimple fracture. There were no cracks and delamination when the 2Cr13/316L composite plate bent to 130° and 180°, which indicated better interfacial bonding.

In this work, a N-doped CsTi2NbO7@g-C3N4 (NTCN) heterojunction nanocomposite was synthesized by a simple one-step calcination method. The as-prepared samples were characterized by means of X-ray diffraction patterns, scanning electron microscopy, high-angle annular dark-field scanning transmission electron microscopy, and Fourier transformed infrared spectroscopy. The results showed that g-C3N4 was formed both on the surface and within the interlayers of CsTi2NbO7, in which CsTi2NbO7 was in situ doped by nitrogen atoms to form N–CsTi2NbO7. The NTCN composite displayed higher electrocatalytic activity toward the detection of nitrite than pure CsTi2NbO7 and g-C3N4. The main reasons could be attributed to the synergistic effects of morphology engineering, N-doping, and layered heterojunction. The NTCN-based electrochemical sensor expressed a good linear relationship range from 0.0999 to 3.15 mmol/L with a detection limit of 2.63 × 10−5 mol/L. The good recovery, stability, and reproducibility of this biosensor showed the potential application in environmental monitoring.

Due to extremely high conductivity of copper (Cu), copper–based nanocomposites offer remarkable opportunities for use in energy conversion and storage. Their applications demand low-cost syntheses routes relying on using inexpensive equipment with no formation of hazardous wastes. In this work, we report on a novel, cheap and environmentally friendly synthesis and application of nano-porous Cu as a support for lithium titanate. The infiltration of lithium titanate onto the inner surface of NPCu produced high-rate anodes for Li-ion batteries capable of providing nearly 50mAh/g during about 20s charging while retaining about 70% of the initial capacity after 1000 charge-discharge cycles. The demonstrated versatility and simplicity of this fascinating approach show great promises for scalable production and the use of NPCu in various cost-sensitive applications.

This study aimed to investigate the effects of dietary live yeast (LY) supplementation on growth, intestinal permeability and immunological parameters of piglets challenged with enterotoxigenic Escherichia coli K88 (ETEC). Piglets weaned at 21 d were allocated into three treatments with six pens and six piglets per pen, receiving the control diet (CON), diets supplemented with antibiotics plus zinc oxide (ANT–ZnO) and LY (Saccharomyces cerevisiae strain CNCM I-4407), respectively, for a period of 2 weeks. On day 8, thirty-six piglets were selected as control without ETEC (CON), CON–ETEC, ANT–ZnO–ETEC and LY–ETEC groups challenged with ETEC until day 10 for sample collections. Piglets fed ANT–ZnO diet had the highest average daily gain and average daily feed intake (P<0·05) during the 1st week, but ADG of piglets fed the ANT–ZnO diet was similar as piglets fed LY diet during the second week. Piglets with LY–ETEC or ANT–ZnO–ETEC had markedly lower diarrhoea score (P<0·05) than piglets with CON–ETEC during the 24 h after ETEC challenge. Relative to piglets with CON, the counts of E. coli, urinary ratio of lactulose to mannitol, plasma IL-6 concentration, mRNA abundances of innate immunity-related genes in ileum and mesenteric lymph node tissues were increased (P<0·05), whereas the villous height of jejunum and relative protein expression of ileum claudin-1 were decreased (P<0·05) in piglets with CON–ETEC; however, these parameters did not markedly change in piglets with LY–ETEC or ANT–ZnO–ETEC. In summary, dietary LY supplementation could alleviate the severity of diarrhoea in piglets with ETEC, which may be associated with the improved permeability, innate immunity and bacterial profile.

There is a substantial controversy in the economics literature over the magnitude of the expenditure elasticity for food grain in China that is caused, to a large extent, by whether time-series or cross-section data are used in the analysis. A set of reasonable elasticities for a complete demand system is estimated by using a panel of county level data in Guangdong Province for the last ten years. The results show that food grain has a small positive income elasticity, implying that food grain is not an inferior good in China. The reason that consumption per capita has not increased during a period of rapid economic growth in income is that the relative prices of the food and non-food substitutes for food grain have decreased.

Zeolite–zeolite composite composed of alumina-rich hierarchically porous ZSM-5 cores and high-silicon MFI shells was prepared by a hydrothermal synthesis procedure, in which a commercial ZSM-5 zeolite with a SiO2/Al2O3 of 36 was treated by an alkaline solution and then used as a supporter for epitaxial growth of a polycrystalline Silicalite-1 zeolite shell (denoted as MMZsa). Acid sites associated with framework Al on exterior surfaces of ZSM-5 zeolite cores are therefore passivated in different degrees by the epitaxial MFI zeolite shell. The structural, crystalline, and textural properties of the as-synthesized samples were characterized by x-ray powder diffraction (XRD), energy-dispersive x-ray spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), N2 adsorption-desorption, in situ IR spectra of pyridine and NH3-TPD. Aluminum species were observed to transfer from the alumina-rich cores to the high-silica shells. The adjustable thickness and SiO2/Al2O3 ratio of the shell offer the as-synthesized composite a potential and high-efficiency catalyst for methanol conversion into gasoline and diesel. As compared with the commercial ZSM-5 zeolite, the composite catalyst exhibits excellent catalytic performances with a longer catalytic life as well as a higher conversion and a slightly higher yield of diesel oil.

Excellent sites are necessary for developing and installing ground-based large telescopes. For very-high-resolution solar observations, it had been unclear whether there exist good candidate sites in the west areas in China, including the Tibetan Plateau and the Pamirs Plateau. The project of solar site survey for the next-generation large solar telescopes, i.e., the Chinese Giant Solar Telescope (CGST) and the large coronagraph, has been launched since 2011. Based on the close collaboration among Chinese solar society and the scientists from NSO, HAO and other institutes, we have successfully developed the standard instruments for solar site survey and applied them to more than 50 different sites distributed in Xinjiang, Tibet, Qinghai, Sichuan, Yunnan and Ningxia provinces. We have built two long-term monitoring sites in Tibet and the large Shangri-La to take systematic site data. Clear evidence, including the key parameters of seeing factor, sky brightness and water vapor content, has indicated that a few potential sites in the large Tibetan areas should obtain the excellent astronomical conditions for our purpose to develop CGST and large coronagraph. We introduce the fresh site survey results in this report.

TiO2 has attracted tremendous research interest for photocatalytic water splitting, solar hydrogen generation, environmental pollution removal, dye-sensitized solar cells, lithium-ion batteries, supercapacitors, and field emission. Microwave absorption materials (MAMs) play important roles in many military (e.g., the stealth coating on the B-2 bomber) and civil (e.g., telecommunications, noise reduction, information security, signal, and data protection) applications. However, TiO2 is not a good MAM due to its poor absorption in the microwave region. Here, we report that via hydrogenation excellent and tunable microwave absorption is achieved with hydrogenated TiO2 nanocrystals. After hydrogenation, 4.3x and 103x improvements have been obtained in storing and dissipating the electric energy of the microwave electromagnetic field. Their permittivity values are higher than those of the current carbonaceous MAMs. Instead of relying on the dipole rotation or ferromagnetic resonance mechanisms for traditional MAMs, the hydrogenated TiO2 nanocrystals work as good MAMs based on a newly proposed collective-movement-of-interfacial-dipole (CMID) mechanism. Although there is still no direct physical evidence of the interface effects of the CMID mechanism, the CMID as a hypothesis at this point successfully explained the origin of the enhanced microwave absorption of the hydrogenated TiO2 nanoparticles. This study thus may open new applications for TiO2 nanocrystals and also stimulate new approaches for new MAM development.

Utilizing SOHO/MDI data of two active regions (ARs 08398 & 10373), we identify and trace the whole lifetimes of 26 positive and 68 negative unipolar Moving Magnetic Features (MMFs). The statistical properties of several kinematic and magnetic quantities are studied.

Single crystals of KBeBO3F (KBBF) up to 2 mm in thickness were grown by using a spontaneous nucleation method. The flux was composed of KF and B2O3, and the optimal ratio for growing KBBF single crystal thicker than 1 mm is suggested to be (1.0–1.5):(5.0):(0.7–1.2) (KBBF:KF:B2O3) in molar ratio. The ideal morphology of.KBBF is two sets of tabular facets and a set of rhombic facets. Surface morphology.was characterized both by optical microscopy and atomic force microscopy. Transmission spectra showed that high transmission was maintained up to 170 nm. Based on refractive index measurements, phase matching curves for types I and II were determined. Using a prism coupling method, the effective fourth harmonic generation for an Nd:YAB laser was realized in an 0.6-mm-thick KBBF sample. The output energy of the 266-nm beam was 0.282 mJ, and the conversion efficiency was 11.8%. A 183.6-nm laser over 1 mW was obtained from a Ti:sapphire second harmonic generation beam in an 0.8-mm KBBF sample. The conversion efficiency reached 2.3%. A 179.4-nm laser was also observed from a 358.7-nm laser by directly frequency doubling. This is the shortest wavelength obtained through nonlinear optical processes in a solid-state laser.