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Melanoma is one of the highly malignant tumors whose incidence and fatality rates have been increased year by year. However, in addition to early surgical resection, there still lacks specific targeted drugs and treatment strategies. In this study, it was discovered that hinokiflavone (HF) encapsulated in zeolitic imidazolate framework-8 (ZIF-8) exhibited a superior anti-melanoma effect

Increasing forage yield and nutritional quality under the premise of maintaining relatively stable land area and soil nutrient content is a necessary condition for the sustainable development of grassland animal husbandry. Different cutting models [simulated grazing (SG), hay harvesting (H)] of oat (Avena sativa), common vetch (Vicia sativa) and their mixture (Avena sativa + Vicia sativa) were studied on the Loess Plateau. The results show that (1) SG could increase forage yield, crude protein, and crude fat content and decrease crude ash content. In 2014, the yield of Avena sativa per hectare was 3,578.11 kg higher than that of H; (2) the model analysis for predicting nutritional components showed that the Crude protein (CP) and EE contents of forages in each variety (combination) showed a linear downward trend with increasing forage yield. Redundancy analysis showed that precipitation, especially in the growing season, was positively correlated with grass yield and CP content; and (3) there were significant differences in soil organic carbon, total nitrogen, NO3−-N, and NH4+-N contents for the different forage varieties (combinations) under different use modes; the values first decreased, then increased, and finally decreased. According to the comprehensive evaluation value calculated by Technique for Order Preference by Similarity to an Ideal Solution, mixed sowing was better than monoculture, and SG obtained better results than H. Overall, mixed sowing under SG can improve forage yield and nutritional quality. At the same time, precipitation regulation is the key factor affecting the production performance of rainfed cultivated grassland on the Loess Plateau.

The region between the Loess Plateau and the Qinghai-Tibetan Plateau is an important ecological zone in China which is located in the transition zone of continental plate from the second step terrain to the first step terrain. The local people in the area mainly depend on crops, livestock and crop and livestock integration. The crop and livestock integration is strongly interrelated to ecological characteristics of the region and the human activities. In this study we investigated the key factors for economic benefits of farming systems and social structure along a transect of the region; Tongwei (TW), Weiyuan (WY) and Xiahe (XH). The data for the study was obtained by the statistical year book of China. The key factors for input and output of different crop production systems and livestock systems were used for the study. We used Logistic regression model to examine the relationship of proportion of farmers in the population and the productivity of the faming system (based on input vs output). We found a significant correlation between proportion of farmers and the farmer productivity ( P WY (12.65×103 ¥/farm) > XH (−2.68×103 ¥/farm). Livestock production system: The total inputs for livestock farming and the natural grassland area increased east to west of the region. The total output was intermediate in WY. The economic benefits of different livestock systems were: pig (0.14×103 ¥/farm), sheep (1.84×103 ¥/farm) and cattle (32.79×103 ¥/farm) in TW, WY and XH respectively. Integrated production system: The response rates of proportion of farmers to input were 1.30, 0.61 and 0.70 for XH, TW and WY respectively. In contrast, the response rates of proportion of farmers to output were 0.085, 0.17, and 0.37 in XH, TW and WY. The threshold value for economic benefits and the proportion of farmers remained 50%. The economic benefits of the three study areas were: XH (30.27×103 ¥/farm) >TW (20.22×103 ¥/farm)>WY (13.07×103 ¥/farm). When the proportion of farmers were above the threshold point, the inputs of TW, WY and XH increased 45.76%, 47.98% and 45.60% respectively, and the output increased 43.20%, 42.60% and 45.60% respectively. The economic benefits at the threshold points were 30.52, 16.32 and 64.70×103 ¥/farm in TW, WY and XH respectively. The natural resources and agricultural population varied east to west of the study transect and the farming systems changed cropping to grazing. Labor was the largest input in all production systems. Our study indicates that regulating and controlling the proportion of farmers is an effective measure to realize the ″win-win″ scenario of economic and ecological benefits. We found that compared to crop production systems, the livestock production system and integration of crop and livestock are effective means of improving agricultural productivity, environmental sustainability and farmers′ income.

There are more or less dopants or defects existing in nanomaterials, so they usually have different conduct-types even for the same substrate. Therefore, fast identification of the conduction-type of nanomaterials is very essential for their practical application in functional nanodevices. Here we use the field emission (FE) technique to research nanomaterials and establish a generalized Schottky-Nordheim (SN) model, in which an important parameter λ (the image potential factor) is first introduced to describe the effective image potential. By regarding λ as the criterion, their energy-band structure can be identified: (a) λ = 1: metal; (b) 0.5

Lanthanum hexaboride (LaB6) nanostructures have attracted much attention in recent years because they exhibit high electrical conductivity and thermal conductivity, low work function and high chemical stability, and can be expected to be an ideal cold cathode electron source for power device applications. Although some groups have developed means to grow LaB6 nanostructures and investigated their emission properties, the moderate synthesis of the LaB6 nanostructure cathode with high-performance is still a challenging issue. Here we developed a simple one-step chemical vapour deposition (CVD) method to prepare the LaB6 nanowire cold cathode film. The LaB6 nanowires have a mean length of tens of micrometres and their average diameter is about 100 nm. The formation of the nanowires is attributed to the synergy of the vapour–liquid–solid (VLS) and vapour–solid (VS) mechanisms. The LaB6 nanowires are found to have a low turn-on (2.2 V μm−1) and threshold field (2.9 V μm−1) as well as nice field emission (FE) stability with a current fluctuation of only 1.7%. And their emission current can reach 5.6 mA (16.7 mA cm−2) at 4.1 V μm−1, which is large enough for the high-current requirements of cathodes used in power devices. Moreover, the LaB6 nanowires still retain excellent performance even if the operation temperature is raised up to 773 K. It is noted that the LaB6 nanowire film exhibits quite different emission behaviours during a temperature cycling between room temperature and 773 K. The adsorption and desorption of oxygen onto and from the nanowire's surface is suggested to explain the discrepancy of such emission properties based on a series of our designed experiments. Most importantly, the LaB6 nanowire cathode film can almost recover to the original excellent FE performances after detachment of the surface oxygen molecules, which suggests that they should be ideal cathode nanomaterials for power device applications.

SmB 6 is believed as an ideal candidate for FE applications because of their unique properties. Up to date, the effect of image potential on the field emission (FE) behaviors of one-dimensional nanostructures is still unclear in experiments, and thus it becomes a challenging issue for the researchers. In this paper, the effect of image potential on FE properties of SmB 6 nanowires are detailed studied by combination of experimental results and the generalized Schottky-Nordheim (SN) model. The experimental results show that they have a turn-on field of 3.4 V/μm (at 10 μΑ/cm2). Meanwhile, the image potential factor of SmB 6 nanowires is calculated to be equal to 1 based on our model, which is resemble to ideal metal plane.

Lanthanum hexaboride (LaB 6 ) nanowires have attracted much attention due to their outstanding physical properties. In order to enhance the developments of LaB 6 nanowires, it is essential to study the field emission (FE) properties of LaB 6 nanowires in different environments. Here, we investigate the effect of oxygen (O 2 ) on the FE behaviors of LaB 6 nanowires. And it is found that the oxygen content attaching on the surface of LaB 6 nanowires strongly affect their FE properties.

As China's urbanization gradually enters the era of 'urban circle' and 'urban agglomeration', the suburban railway which is regarded as the way of connecting urban centers and suburban areas, such as Satellite city, as well as reshaping the layout of urban space, has been highly praised by the central government. In May 2017, the five ministries and commissions jointly issued the guidance on 'promoting the development of the urban suburban railway'. In the guidance, it is clear that the effective supply of the transit service of the suburban railway should be expanded. But in China, the city railway system and city traffic system belong to different traffic management department, and another problem which leads to such situation is that the division of labour and the function of railway system and urban traffic system are different for a long time. So how to operate the suburban railway in Beijing is an significant problem that needed to be solved.

As a typcial kondo insulator, SmB 6 has attracted most of attention in recent years. But their corresponding nanostructures are hard to fabricate due to the growth technique. In this paper, uniform SmB 6 nanocone arrays have been successfully fabricated by a simple chemical vapor deposition (CVD) method. The field emission (FE) behaviors of SmB 6 nanocone arrays were investigated to reveal their surface properties. FE measurement results show that SmB 6 nanocone arrays have a low turn-on electric field of 1.84 V/μm (at 10 μA/cm2) and good emission stability, which may have potential applications in FE area.

The B/LaB 6 hierarchical heterojunction nanostructures have been successfully fabricated on Si substrate by CVD technique. The branch-like morphology may be beneficial to improving their field emission (FE) properties by increasing the aspect ratio or growth density of the emitters. The results show that the threshold field of the B/LaB 6 branch-like nanoheterojunctions is 21.6 V/μm (@1 mA/cm2) and their maximum field current density can reach 4.8 mA/cm2 (at 27.5 V/μm). It is suggested a novel Ohmic-contact LaB 6 nanoheterojunction to promote their rapid applications in FE area in future.

Boron is a narrow-bandgap (1.56 eV) semiconductor with high melting-point, low-density, large Young's modulus and very high refractive index (3.03) close to silicon. Therefore, boron nanostructures is expected to possess strong visible-light scattering properties. However, photonic and optoelectronic properties of the boron nanostructures are seldom studied until now. In this paper, we have successfully prepared single-crystalline boron nanowire (BNW) arrays with high-density on Si substrate. All the BNWs are found to possess strong light-scattering behaviors in the visible regime. Most of all, the scattered light is found to polarize along the longitudinal direction of the nanowire. They also have excellent second-harmonic generation (SHG) properties under ultrafast laser irradiation. Further optoelectronic measurements show that an individual BNW device exhibits notable photocurrent responses in the visible-light range at ambient conditions, which can be attributed to the strong coupling effect between individual BNW and the visible light. The maximum photoresponsivity of an individual BNW can reach up to 12.12 A W-1 at a voltage of 10 V, and the response time is only 18 ms. Therefore, it unveils that the BNWs have a promising future in visible-light communications and detections.

Boron nanostructures (nanowires and nanotubes) have been thought as ideal nanomaterials for building optoelectronic nanodevices because of their high conductivity, large elastic modulus and high melting-point. In our studies, it is found that boron nanostructures have a low turn-on field and high emission uniformity. Moreover, boron nanostructures can endure a high emission current, which suggests that they may have potential application in field emission area.

WO2 nanowires have great potential as cold cathode materials because they exhibit excellent field-emission properties in terms of their low work function and high conductivity. Considering the requirements of the practical applications in large-area cold-cathode devices, such as X-ray source and panel display, these nanostructures are desired to be fabricated on glass substrate and integrated into devices. It is best known that the studies on WO2 nanowire cold cathode arrays grown on glass-substrate are absent so far, which remains a challenge for the researchers. In the current study, procedures for fabrication of WO2 nanowire cold cathode arrays, which consist of 22000 separated patterns on 1.2 in. glass wafer are developed. It is found that the turn-on and threshold field of the nanowire arrays are, respectively, 6.6 and 9.3 V µm−1. In addition, the performance of the cold cathode arrays is strongly affected by the distribution of the nanowire density as well as the thickness of Al electrode. By modifying the fabrication techniques, over 82% patterns can contribute to the emission, whereby a maximum current density can reach 1.89 mA cm−2. Such a value can fulfill the basic requirement of the large-area cold cathode devices. The research can pave the way for fabrication of high-performance cold cathode devices using glass-substrates.

Field emission display is a competitive technology for next generation flat-panel displays. Self-assembled nanomaterial cold cathodes are easier to fabricate than Spindt-type tip arrays and therefore low cost fabrication on large area could be achieved [1]. In this study, dual-gate-structure vacuum electron source arrays using CuO nanowire field emitters were fabricated and their potential application in field emission display has been explored.

p-type Sb2Te3/poly(3,4-ethylenedioxythiophene) (PEDOT) thermoelectric composites are fabricated by embedding PEDOT into Sb2Te3 matrix. The grains of Sb2Te3 in the composites are found to be in micron degree and keep plate-like shapes. The measurements of thermoelectric properties show that the thermal conductivity κ of the composites is about 0.14 W m−1 K−1 in the temperature range of 300–523 K, much lower than that of Sb2Te3 compounds. The maximum of dimensionless figure of merit of the composites reaches to 1.18 at 523 K, which is the highest value for the reported Sb2Te3/organic composites. It is suggested that the plate-like Sb2Te3 grains and the embedded PEDOTs may play a significant role in decreasing the thermal conductivity. Furthermore, results of the thermal cycling between the room temperature and 523 K for 50 cycles show that the composites are stable with κ remaining a low value.