Convenient design of anti-wetting nano-Al/WO_(3)metastable intermolecular composites(MICs)with an enhanced exothermic life-span

For solving the dilemma of the short exothermic life-span of WO_(3)based metastable interstitial composites(MICs)with extensive application prospect,this paper has firstly designed the promising antiwetting Al/WO_(3)MICs via electrophoresis assembly of nano-Al and WO_(3)particles fabricated by hydrothermal synthesis method,followed by the subsequent fluorination treatment.A combination of X ray diffraction(XRD),field emission scanning electron microscope(FESEM),energy dispersive X-ray spectroscopy(EDX),and Fourier transform infrared spectroscopy(FT-IR)techniques were utilized in order to characterize the crystal structure,microstructure,and elemental composition distribution of target films after different natural exposure tests.The product with uniform distribution and high purity possesses a high contact angle of~170°and a minute sliding angle of~1°,and displays the outstanding anti-wetting property using droplets with different surface tensions.It also shows great moisture stability in high relative-humidity circumstances after one year of the natural exposure experiment.Notably,the heat output of a fresh sample can reach up to 2.3 kJ/g and retain 96%after the whole exposure test,showing outstanding thermo-stability for at least one year.This work further proposed the mechanism of antiwetting Al/WO_(3)MICs considering the variation tendency of their DSC curve,providing a valuable theoretical reference for designing other self-protected MICs with a long exothermic life-span applied in wide fields of national defense,military industry,etc.

Post-fledging dispersal and habitat use of a reintroduced population of the Crested Ibis (Nipponia nippon)

Background: Knowledge of dispersal movement of birds and their habitat preference during the post-fledging period is fundamental to the understanding of their ecological and evolutionary processes. The Crested Ibis is now being reintroduced to protected sites within its historical range, with the goal of establishing a self-sustaining population that may eventually qualify the species for delisting.Methods: We carried out an ecological study of post-fledging dispersal and habitat use of a reintroduced population of the Crested Ibis(Nipponia nippon) from 2008 to 2012 in Ningshan County, China, by using banding and radio-telemetry methods.Results: In about two weeks(an average of 14.3 days) after fledging, the activities of the fledglings were concentrated in a range of about 100 m around their natal sites, such as the oak-pine forest patches at the edge of open habitats.During this period, fledglings were still partially dependent upon parental care and fed typically on a daily basis.Siblings increasingly became independent by mid-August and then gradually moved away from their natal sites to post-fledging dispersal locations. During the period of the post-fledging dispersal process, most juveniles moving southwest were concentrated at the mean direction(μ = 254.6°, ? = 70.5°) with a mean dispersal distance of 5.1 km.It took an average of 56.4 days to disperse from the natal territory to the first wintering area. Also, forging habitats for juvenile ibis varied with time and local conditions. For example, paddy fields were used most frequently among all habitat types, while shallow rivers just from August to October. Masson pine(Pinus massoniana) was often regarded as the roosting tree species preferred by the Crested Ibis, with the highest utilization rate among all the roosting habitat types. The juveniles of the wild population dispersed four times as far as that of the reintroduced population, but the overall pattern of post-fledging dispersal is similar for the reintroduced and wild populations.Conclusions: Our results are very useful for us to predict the distance and direction of dispersal under various landscape conditions in other released sites. The project is a good example for reintroducing endangered species to their former ranges, and will be valuable for the protection of reintroduced populations of this critically and other endangered species.

Taxonomic Revision of Raorchestes menglaensis(Kou,1990)(Amphibia:Anura),with Descriptions of Two New Species from Yunnan,China

Raorchestes is a group of Bush frogs mainly distributed in South and Southeast Asia that are poorly recognized by morphological criteria.We recognize the true R.menglaensis(Kou) based on 10 specimens newly collected from the type locality.An expanded description is also provided,and we delist the recently reported record,R.parvulus(Boulenger) from China.Combing with morphological and molecular data,two new species are respectively described from Menghai and Lvchun,Yunnan,China.Raorchestes hillisi sp.nov.is distinguished from all other congeners by the following combination of morphological characters:(1) small body sized(males 15.9-17.7 mm,n=7;female 17.5 mm,n=1);(2) head longer than wide;(3) snout longer than eye diameter;(4) the tip of upper jaws slightly notched;(5) internasal space slightly less than interorbital space;(6) tympanum distinct;(7)fingers lacking lateral dermal fringe;(8) outside of toe Ⅰ and both sides of toe Ⅱ lacking lateral dermal fringe,other toes having weak lateral dermal fringes;(9) rudimentary web on toes;(10) lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of fingers and toes not orange.Raorchestes huanglianshan sp.nov.is distinguished from all other congeners by the following combination of morphological characters:(1) small body size(males 17.0-19.6 mm,n=12;female 21.5 mm,n=1);(2) head slightly wider than long or equal;(3) snout longer than eye diameter;(4)the tip of upper jaws slightly notched;(5) internasal space distinctly less than interorbital space(6) tympanum distinct;(7) fingers lacking lateral dermal fringe;(8) toes lacking lateral dermal fringe;(9) rudimentary web on toes;(10)lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of all fingers and toes orange or parts of them orange in life.

磁参数法用于评估NiCr基合金热喷涂层结合强度的研究

本文提出了一种基于饱和磁滞回线特征参数的热喷涂层与基材结合强度的无损测试方法。采用MA-WF-05型磁滞多参数评估系统,对在#45碳钢基材上制备的系列NiCr基合金涂层进行了测试,同时对上述样品采用拉伸试验方法测试了结合强度。并通过多元回归分析方法建立了涂层结合强度的预测方程。结果表明预测值与拉伸试验测试值的平均偏差为3.25%,该方法有望推广应用于其他热喷涂层样品。

基于6,13-双氰基并五苯一维滑移堆积微米带状晶体的双极性电荷传输

基于有机π共轭体系的一维自组装微纳米材料(1D-MNMs)具有较少的散射电荷传输、尺寸适中、易于制备等优点,可以方便地构筑集成微电路.虽然基于p沟道或n沟道有机半导体的一维自组装微纳米材料已经取得了巨大的进展,但遗憾的是,迄今为止,基于双极性有机半导体的一维自组装微纳米材料还非常缺乏.本文利用物理气相传输法,制备了基于6,13-双氰基并五苯(DCP)的一维滑移堆积新型自组装微纳米材料,其表现出良好的双极性电荷传输特性,电子和空穴迁移率分别达到0.34和0.38 cm2 V^(-1)s^(-1),是一维自组装微纳米材料中最好的双极性电荷传输特性之一.此外,基于双极性DCP的一维自组装微纳米材料构建了互补型反相器,增益可达7,表明其在有机逻辑电路中具有潜在的应用前景.

First Asian fossil record of Platydictya (Amblystegiaceae) from the lower Miocene and its paleoenvironmental significance

Mosses form a diverse land plant group in modern vegetation but have rarely showed up in the fossil record compared with vascular plants. Here, we report an extraordinarily-preserved early Miocene moss fossil from the lower Laoliangdi Formation in the Pingzhuang Coal Mine in Chifeng, Inner Mongolia Autonomous Region, northern China. Although lacking rhizoids and most reproductive organs, the well-preserved fossil allows us to assign it to Platydictya cf. jungermannioides (Amblystegiaceae) based upon its detailed gross and micro-morphology. The diagnostic characteristics include a small-sized body with slender stems bearing spirally arranged ovate-lanceolate leaves that lack costae. Leaf margins are mostly partly entire and partly dentate, a few dentate, and rarely completely entire. It represents the first fossil record of Platydictya in Asia. The specific living microenvironment of the extant P. jungermannioides enriched our understanding of the early Miocene environment that was previously based upon vascular plant fossils and sedimentary lithofacies in the area. Our early Miocene Platydictya cf. jungermannioides fossil lived in a warm and humid lush forest with a dense understory that received adequate water supplies.

Copper-promoted domino cyanation/Ullmann coupling toward difunctionalized acenaphthylenes with various optoelectronic properties

Tremendous progress has been made on aromatic fusion of acenaphthylene towards organic semiconductors.However,scarce studies focus on the functionalization of acenaphthylene without resort to aromatic extension,although vinylene double bond is highly reactive ascribed to the ring strain of the fused cyclopentene.Herein,for the first time we employ copper-promoted domino cyanation/Ullmann coupling to achieve a series of difunctionalized acenaphthylene imides(ANIs)with varied optoelectronic properties.Both Ullmann homocoupling and crosscoupling can be combined with cyanation for difunctionalization of ANIs.The introduction of cyano groups influences oppositely not only the energy levels but also the antiaromaticity of the fivemembered rings in ANIs relative to the dimethylamino substituent due to the electron donating or withdrawing effects.By altering the functional units,the optical and electrical characteristics have been tailored rationally;thus p,n or ambipolar semiconducting properties can be achieved for the ANI derivatives.This article opens up possibilities to the development of organic semiconducting materials based on ANIs without aromatic extension,which is promising for applications in organic electronics.

Maternal genetic structure in ancient Shandong between 9500 and 1800 years ago

Archaeological and ancient DNA studies revealed that Shandong,a multi-culture center in northern coastal China,was home to ancient populations having ancestry related to both northern and southern East Asian populations.However,the limited temporal and geographical range of previous studies have been insufficient to describe the population history of this region in greater detail.Here,we report the analysis of 86 complete mitochondrial genomes from the remains of 9500 to 1800-year-old humans from12 archaeological sites across Shandong.For samples older than 4600 years before present(BP),we found haplogroups D4,D5,B4 c1,and B5 b2,which are observed in present-day northern and southern East Asians.For samples younger than 4600 BP,haplogroups C(C7 a1 and C7 b),M9(M9 a1),and F(F1 a1,F2 a,and F4 a1)begin to appear,indicating changes in the Shandong maternal genetic structure starting from the beginning of the Longshan cultural period.Within Shandong,the genetic exchange is possible between the coastal and inland regions after 3100 BP.We also discovered the B5 b2 lineage in Shandong populations,with the oldest Bianbian individual likely related to the ancestors of some East Asians and North Asians.By reconstructing a maternal genetic structure of Shandong populations,we provide greater resolution of the population dynamics of the northern coastal East Asia over the past nine thousand years.

Ancient water wells reveal a prolonged drought in the lower Yellow River area about 2800 years ago

Proxy records from the North Atlantic realm reveal that large and rapid cooling known as the Bond events continued into the Holocene [1],repeatedly punctuating what is conventionally thought to have been a relatively stable climate.Given that the Holocene is the most recent interglacial period that has spurred the development of modern societies,scrutinizing climate variabil- ity during this period is important not only for predicting the trend of future climate changes,but also for better understanding the driving forces behind the rise and fall of ancient civilizations.