Design and fabrication of antibacteriaｌ nanocoatings on cotton and silk fibers through supramolecular self-assembly technology （超分子自己組織化技術による綿およびシルク繊維の抗菌性ナノコーティングに関する研究）

信州大学(Shinshu university)博士（工学）ThesisXU SIJUN. Design and fabrication of antibacteriaｌ nanocoatings on cotton and silk fibers through supramolecular self-assembly technology （超分子自己組織化技術による綿およびシルク繊維の抗菌性ナノコーティングに関する研究）. 信州大学, 2016, 博士論文. 博士（工学）, 甲第661号, 平成28年09月30日授与.doctoral thesi

Spatial-temporal Characteristics and Source Apportionment of Ambient VOCs in Southeast Mountain Area of China

Seasonal variations and sources of ambient volatile organic compounds (VOCs) were conducted at the county and rural sites in a mountain area of southeastern China. The results showed that the pattern of VOC concentrations was dominated by oxygenated VOCs (37.6%) and alkanes (25.8%), followed by halocarbons (16.8%), alkenes (11.9%), aromatics (6.87%), and alkynes (1.04%). Based on the OH radical loss rate (LOH) and ozone formation potential (OFP) analysis, alkenes had the highest chemical activity, especially the contribution of isoprene in rural areas. Aromatics contributed the most to secondary organic aerosols (SOA) formation in both county and rural areas. Source apportionment of VOCs were quantified by the positive matrix factorization (PMF) model, including industrial emissions and combustion burning (30.1% and 43.3% in the county and rural areas, respectively) and vehicle exhausts (30.3% and 10.8%), followed by solvent usage (17.1% and 5.2%), liquid petroleum gas (LPG) usage and fuel evaporation (14.2% and 10.0%), and biogenic source (8.3% and 30.6%). The backward air trajectories showed that air mass in spring was mainly originated from the intercity transmission, while the air clusters in autumn came from the northern areas through long-range transport. The study was helpful to understand the pollution characteristics in the mountainous area and provides a scientific basis for local O3 and PM2.5 pollution control

Short-term load forecasting based on sample weights assignment

Short-term load forecasting (STLF) is the basis of the power system operation. Considering that the importance of different training samples is different, a sample weights assignment method is proposed in this paper to help the STLF to learn the key sample. At first, the sample similarity is measured considering the characteristics of different input components. Based on this, training samples are selected. Finally, different training samples are assigned with different sample weights through the designed weights assignment function. With the proposed method, the STLF model is able to focus on the crucial samples. Simulation results considering different data-driven models demonstrate the effectiveness of the proposed method

Effect of glucose on the soil bacterial diversity and function in the rhizosphere of Cerasus sachalinensis

Most cherry orchards in China have low organic carbon content, though carbon is very important for plant growth. The changes in soil carbon and bacterial diversity were determined after different amounts of 12C-glucose were added to the rhizosphere of Cerasus sachalinensis. Soil bacteria diversity was measured using high throughput sequencing, and bacteria containing 13C-glucose were identified using DNA-SIP methods. The results demonstrated that soil microbial biomass carbon (MBC) content and the soil respiratory rate were increased at 3 and 7 days after adding glucose. The soil organic carbon (SOC) content was decreased on the 7th day in the treatment where the added glucose-C was equivalent to the MBC content. SOC content was decreased on the 15th day after adding glucose-C equivalent to five times that of the soil MBC. Compared to the controls, the relative abundance of taxa at the phylum level displayed no significant change in the treatments with glucose-C added as 10% and equal amount of soil MBC 3–30 days after treatment. However, the relative abundance of Proteobacteria increased significantly in the treatment with the addition of glucose-C equivalent to five times of soil MBC. The main changes were observed in the bacteria in several genera including A4, Flavisolibacter, Aquicella, and Candidatus Solibacter. DNA-SIP results indicated that the relative abundance of the Proteobacteria and Pseudomonas was the highest; these were the primary bacteria phylum and genus, respectively, from day 3 to day 15. In conclusion, the changing pattern demonstrated that with the addition of more glucose, the range of the bacterial communities changed more. Proteobacteria and Pseudomonas may be the bacteria promoting priming effect

Activated Carbon Fibers “Thickly Overgrown” by Ag Nanohair Through Self-Assembly and Rapid Thermal Annealing

Abstract Anisotropic nanomaterial-modified carbon fibers attract increasing attention because of their superior properties over traditional ones. In this study, activated carbon fibers (ACFs) “thickly overgrown” by Ag nanohair were prepared through self-assembly and rapid thermal annealing. Viscose fibers with well-dispersed silver nanoparticles (AgNPs) on surfaces were first prepared through self-assembly of hyperbranched poly(amino-amine) (HBPAA)-capped AgNPs on viscose surfaces. HBPAA endowed the AgNP surfaces with negative charges and abundant amino groups, allowing AgNPs to monodispersively self-assemble to fiber surfaces. Ag nanohair-grown ACFs were prepared by sequential pre-oxidation and carbonization. Because the carbonization furnace was open-ended, ACFs are immediately transferrable to the outside of the furnace. Therefore, the Ag liquid adsorbed by ACF pores squeezed out to form Ag nanowires through thermal contraction. FESEM characterization indicated that Ag nanohairs stood on ACF surface and grew from ACF caps. XPS and XRD characterization showed that Ag successfully assembled to fiber surfaces and retained its metallic state even after high-temperature carbonization. TG analysis suggested that Ag nanohair-grown ACFs maintained their excellent thermal stabilities. Finally, the fabricated ACFs showed excellent and durable antibacterial activities, and the developed method may provide a potential strategy for preparing metal nanowire-grown ACFs

An Analytic Model of Transient Heat Conduction for Bi-Layered Flexible Electronic Heaters by Symplectic Superposition

In a flexible electronic heater (FEH), periodic metal wires are often encapsulated into the soft elastic substrate as heat sources. It is of great significance to develop analytic models on transient heat conduction of such an FEH in order to provide a rapid analysis and preliminary designs based on a rapid parameter analysis. In this study, an analytic model of transient heat conduction for bi-layered FEHs is proposed, which is solved by a novel symplectic superposition method (SSM). In the Laplace transform domain, the Hamiltonian system-based governing equation for transient heat conduction is introduced, and the mathematical techniques incorporating the separation of variables and symplectic eigen expansion are manipulated to yield the temperature solutions of two subproblems, which is followed by superposition for the temperature solution of the general problem. The Laplace inversion gives the eventual temperature solution in the time domain. Comprehensive time-dependent temperatures by the SSM are presented in tables and figures for benchmark use, which agree well with their counterparts by the finite element method. A parameter analysis on the influence of the thermal conductivity ratio is also studied. The exceptional merit of the SSM is on a direct rigorous derivation without any assumption/predetermination of solution forms, and thus, the method may be extended to more heat conduction problems of FEHs with more complex structures

Physiological and Structural Changes in Apple Tree Branches of Different Varieties during Dormancy

Low temperature is an abiotic stress factor limiting the distribution of fruit tree cultivation areas. As temperate deciduous fruit trees, apple (Malus domestica) trees go dormant in the winter to adapt to or avoid damage caused by low temperatures. The capacity for cold resistance is closely linked to the physiological, biochemical, and structural characteristics of one-year-old branches. In this study, we investigated such changes in the branches of cold-resistant ‘Hanfu’ (HF) and cold-sensitive ‘Naganofuji 2’ (CF) apple varieties. The relative electrical conductivity, malondialdehyde content, and reactive oxygen species content of HF branches were lower than those of CF branches, while the antioxidant enzyme activity was higher in HF. The proline, soluble protein, and soluble sugar contents in both varieties showed an initial increase, followed by a subsequent decrease. Sucrose and sorbitol were the main sugar components, but sucrose and fructose were higher in HF than in CF. The periderm, phloem, and xylem of HF branches were also found to be thicker than those of CF branches, while the vessel diameter was smaller and the density greater. The results of this study provide a theoretical reference for further research on the low temperature adaptability of apple tree branches during dormancy

An Analytical Thermal Buckling Model for Semiconductor Chips on a Substrate

Semiconductor chips on a substrate have a wide range of applications in electronic devices. However, environmental temperature changes may cause mechanical buckling of the chips, resulting in an urgent demand to develop analytical models to study this issue with high efficiency and accuracy such that safety designs can be sought. In this paper, the thermal buckling of chips on a substrate is considered as that of plates on a Winkler elastic foundation and is studied by the symplectic superposition method (SSM) within the symplectic space-based Hamiltonian system. The solution procedure starts by converting the original problem into two subproblems, which are solved by using the separation of variables and the symplectic eigenvector expansion. Through the equivalence between the original problem and the superposition of subproblems, the final analytical thermal buckling solutions are obtained. The SSM does not require any assumptions of solution forms, which is a distinctive advantage compared with traditional analytical methods. Comprehensive numerical results by the SSM for both buckling temperatures and mode shapes are presented and are well validated through comparison with those using the finite element method. With the solutions obtained, the effects of the moduli of elastic foundations and geometric parameters on critical buckling temperatures and buckling mode shapes are investigated

Synergistic Effects of Photocatalytic and Electrocatalytic Oxidation Based On a Three-Dimensional Electrode Reactor Toward Degradation of Dyes in Wastewater

Degradation processes and kinetics of methyl orange (MO) by photocatalytic oxidation (PCO), electrocatalytic oxidation (ECO), and photoelectrocatalytic oxidation (PECO) were investigated using a three-dimensional electrode reactor with TiO2/Ti electrode as anode and TiO2 immobilized on columnar activated carbon (TiO2/CAC) as packed bed particle electrodes. The synergistic effects of PCO and ECO under different anode bias voltages were studied. UV irradiation for generating electron-hole pairs and external bias voltage for promoting the separation of photogenerated holes and electrons were conducive to achieving a synergistic effect during the PECO process, thereby significantly improving the efficiency of degradation. Moreover, under an anode bias voltage of 1.0 V, the degradation efficiency of MO in PECO process reached 98.76% at 35 min, which was much higher than that of in PCO (62.43%) and in ECO (33.93%) processes. The degradation rate constant of the PECO was estimated to be 0.1354 min−1, which was significantly higher than the sum of degradation rate constant of the PCO (0.0260 min−1) and ECO process (0.0114 min−1). This novel three-dimensional electrode reactor has excellent efficiency of degradation by PECO process and shows a great potential application in wastewater treatment