In recent years, the efficient and clean utilization of coal has been widely concerned by scholars at home and abroad. Despite the abundance of global coal resources, the deep utilization rate of coal is still insufficient. To address this challenge, it has been explored the development and preparation of coal-based high value-added carbonaceous materials. In the present study, a novel process was developed for the preparation of graphene using biphenyl sourced from low-rank coal. Using chemical vapor deposition (CVD) technology, it was successfully implemented for us to grow high-quality graphene on copper foils. The prepared graphene products were observed and characterized using Raman spectroscopy, optical microscopy and scanning electron microscopy techniques. The results of this research provide a new perspective for the utilization of low-rank coal resources.
Single-atom Pd clusters anchored on t-BaTiO3 material was synthesized using hydrothermal and ultrasonic methods for the effective piezoelectric catalytic degradation of pollutants using vibration energy. XRD patterns of BaTiO3 loaded with monoatomic Pd were obtained before and after calcining, and showed typical cubic-phase BTO. TEM and HAADF-STEM images indicated single-atom Pd clusters were successfully introduced into the BaTiO3. The piezoelectric current density of the prepared Pd-BaTiO3 binary composite was significantly higher than that of the pristine BaTiO3. Under mechanical vibration, the nanomaterial exhibited a tetracycline decomposition rate of ~95 % within 7 h, which is much higher than the degradation rate of 56.7 % observed with pure BaTiO3. Many of the piezo-induced electrons escaped to the Pd-doped BaTiO3 interface because of Pd’s excellent conductivity. Single-atom Pd clusters help promote the separation of the piezo-induced electrons, thereby achieving synergistic catalysis. This work demonstrates the feasibility of combining ultrasonic technology with the piezoelectric effect and provides a promising strategy for the development of ultrasonic and piezoelectric materials.
Low thermal conductivity carbon fibers from polyacrylonitrile (PAN) are currently being explored as an alternative for traditional rayon-based carbon fibers with a thermal conductivity of 4 W/m K. Compared to multiple component electrospinning, this research demonstrated another feasible way to make low thermal conductivity carbon fibrous material by electrospinning PAN followed by carbonization and alkali activation. The effects of activation condition on microstructure, pore formation, and thermal conductivity of the resultant carbon nanofibrous material were investigated. The processing-structure-thermal conductivity relationship was revealed and mechanism of thermal conductivity reduction was discussed. The overall thermal conductivity of the prepared carbon nanofibrous material is a result of combined effects from factors of carbon structure and number of pores rather than volume of pores or specific surface area. The activated carbon nanofibrous materials showed thermal conductivity as low as 0.12 W/m K, which is a reduction of ~ 99% when compared to that of solid carbon film and a reduction of ~ 95% when compared to that of carbon nanofibrous material before activation.
The KVN(Korean VLBI Network)-style simultaneous multi-frequency receiving mode is demonstrated to be promising for mm-VLBI observations. Recently, other Very long baseline interferometry (VLBI) facilities all over the globe start to implement compatible optics systems. Simultaneous dual/multi-frequency VLBI observations at mm wavelengths with international baselines are thus possible. In this paper, we present the results from the first successful simultaneous 22/43 GHz dualfrequency observation with KaVA(KVN and VERA array), including images and astrometric results. Our analysis shows that the newly implemented simultaneous receiving system has brought a significant extension of the coherence time of the 43 GHz visibility phases along the international baselines. The astrometric results obtained with KaVA are consistent with those obtained with the independent analysis of the KVN data. Our results thus confirm the good performance of the simultaneous receiving systems for the non-KVN stations. Future simultaneous observations with more global stations bring even higher sensitivity and micro-arcsecond level astrometric measurements of the targets.
This study researched the population of ecological characteristics of the goldeyes rockfish Sebasetes thompsoni sampled by gill net in the Ulleungdo area from February 2013 to February 2014 in order to assess the current stock status and provide scientific advice for management implementation. The instantaneous coefficient of total mortality (Z) was 0.78/year and the survival rate (S) was 0.459. The instantaneous coefficient of natural mortality (M) was 0.461/year. Based on the estimates of Z and M, the instantaneous coefficient of fishing mortality (F) was 0.318/year. The age at first capture (tc) was 4.41/years. Current Yield-per-recruit (YPR) was 30.83 g, and fishing mortality at maximum YPR (Fmax) and fishing mortality corresponding to 10% of the maximum slope in YPR curve (F0.1) were 3.257/year and 0.673/year, respectively. F35% and F40%, indicating fishing mortalities at 35% and 40% of maximum Spawning biomass-per-recruit (SBPR), were 0.619/year and 0.509/year, respectively. Based on the biological reference points, fishing mortality at overfished threshold yield (FOTY) was calculated as 0.509/year. Current SBPR/SBPRMSY was 1.313 above 1.0, which means ‘not overfishe,’ while current F/FOTY was 0.629 below 1.0, which indicates ‘not overfishing.’ In conclusion, the current status of goldeyes rockfish was located in green zone (i.e., not overfished and not overfishing) according to the revised Kobe plot.
In recent years, with the development of economy, the proportion of building energy consumption in the national energy consumption is growing. To reduce building energy consumption, has become an important measure to reduce energy consumption, and on the basis of general building sustainability into the design is closely related to residential design. To restrict the problems existing in the cold region residential energy saving construction in our country, the study of cold region in winter heating technology to design, is to summarize a set of suitable heating technology applied in the cold region sustainable residential promotion. The article is divided into five parts, the first part is the introduction, describes the research background, contents, methods, purpose, etc.; The second part mainly introduces the passive solar energy heating technology; The third part mainly introduces the sustainability of residential status and development prospects; The fourth part is how to passive solar heating technology is applied to sustainable residence that is application techniques to explore. The fifth part is through the research, the conclusion and the outlook for the future.
Customer loyalty programs have been widely adopted for customer relationship management all over the world. The proliferation of loyalty programs causes program competition which weakens the effectiveness of loyalty programs at the end of customers. In general, existed research suggests that the increasing competition among rival programs in a single industry may cancel out the expected roles of loyalty programs (Mägi, 2003). For example, program competition is a substantial threat to customer lifetime value and share of wallet (Leenheer, van Heerde, Bijmolt, & Smidts, 2007; Meyer-Waarden, 2007). Liu and Yang (2009) find the sales impact of a single loyalty program diminishes as program competition increases. Their study also shows this negative effect is weaker in a highly expandable product category. Although previous studies have examined the suppressive effect of program competition on financial outcomes of loyalty programs, little research has explored its role on attitudinal customer loyalty formation process. This study aims to explore the differential roles of program competition on two formation processes of customer loyalty. It intends to contribute to the loyalty programs literature in two aspects. First, this study examines two routines of customer loyalty formation in the context of loyalty programs. That is, a company can leverage program offerings to build customer loyalty through increased customer satisfaction or strengthened customer identification with the company. Second, this study examines the moderating roles of program competition on those two loyalty-generating routines. Specifically, it finds customer identification is more important for building customer loyalty at the presence of program loyalty.
In recent years, with the development of economy, the proportion of building energy consumption in the national energy consumption is growing. To reduce building energy consumption, has become an important measure to reduce energy consumption, and on the basis of general building sustainability into the design is closely related to residential design. To restrict the problems existing in the cold region residential energy saving construction in our country, the study of cold region in winter heating technology to design, is to summarize a set of suitable heating technology applied in the cold region sustainable residential promotion. The article is divided into five parts, the first part is the introduction, describes the research background, contents, methods, purpose, etc.; The second part mainly introduces the passive solar energy heating technology; The third part mainly introduces the sustainability of residential status and development prospects; The fourth part is how to passive solar heating technology is applied to sustainable residence that is application techniques to explore. The fifth part is through the research, the conclusion and the outlook for the future.
In this paper, the effect of different land-use types on soil organic carbon (SOC) and Particulate Organic Carbon(POC) was studied by analyzing the soils in the meadow and conversing land of grassland to cropland in ecotones of agriculture and animal husbandry. It is shown t㏊t, compared with meadow, rotations of P/O and P/Cwill reduce SOC in 0-30㎝ soil layers by 47.54%-65.11% and 34.16-64.26% and POC by 16.90%-24.48% and 11.94%-20.29%, respectively. And SOC in meadow is more t㏊n in conversing land of grassland to cropland (P<0.05). Conversing grassland to cropland in ecotones of agriculture and animal husbandry will decrease the contents of SOC and POC.