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International audience; Lanthanides in the trivalent oxidation state are typically described using an ionic picture that leads to localized magnetic moments. The hierarchical energy scales associated with trivalent lanthanides produce desirable properties for e.g., molecular magnetism, quantum materials, and quantum transduction. Here, we show that this traditional ionic paradigm breaks down for praseodymium in the tetravalent oxidation state. Synthetic, spectroscopic, and theoretical tools deployed on several solid-state Pr(4+)-oxides uncover the unusual participation of 4f orbitals in bonding and the anomalous hybridization of the 4f(1) configuration with ligand valence electrons, analogous to transition metals. The competition between crystal-field and spin-orbit-coupling interactions fundamentally transforms the spin-orbital magnetism of Pr(4+), which departs from the J(eff) = 1/2 limit and resembles that of high-valent actinides. Our results show that Pr(4+) ions are in a class on their own, where the hierarchy of single-ion energy scales can be tailored to explore new correlated phenomena in quantum materials.

Xinglinpu Bridge was built on the S3801 freeway in 2019 in preparation for the winter Olympics in Beijing, China. It is a cable-stayed steel bridge with pylons in the shape of flower baskets. Using Xinglinpu Bridge as a case study, a systematic approach to the dimensional quality assessment of complex bridges using a combination of three-dimensional (3D) point clouds obtained by terrestrial laser scanning (TLS) and unmanned aerial vehicle (UAV) surveys is proposed in this paper. The currently available methods for dimensional quality assessment of complex bridges rely largely on manual inspection and contact-type measurement devices, which are time consuming and costly. To overcome these limitations, this paper presents a framework for dimensional quality assessment composed of three parts: scanning schemes for TLS and UAV, scanning implementation and measurement of geometric dimensions. The results of configuration detection verified the high-quality construction of Xinglinpu Bridge, although millimetre-scale differences were obtained between the point clouds and the design value. The potential and limitations of 3D laser scanning for assessing the quality of complex bridges are discussed.

Decorating inorganic particles with core-shell structure is an attractive approach to broaden their practical application owing to the synergistic effects between inner core and outer shell. In this work, a novel rutile TiO2@AlPO4 core-shell composite has been constructed via a facile one-step wet chemical deposition method. The dense and thick AlPO4 shell can hinder direct contact between TiO2 core and outer environment, decrease light absorption ability, suppress separation of electron-hole pairs, and accelerate electron annihilation. Such unique properties hindered the generation of reactive oxygen species, further contributing to the suppression of photoactivity. The superior dispersion stability in aqueous system of TiO2@AlPO4 core-shell hybrid was attributed to its enhanced surface electronegativity. Thus-produced TiO2@AlPO4 core-shell hybrid with suppressed photoactivity and enhanced dispersion stability could further increase the weather durability and prolong the life span of TiO2-based pigment. Overall, this study provides new insight into the mass production of multi-functional rutile TiO2 pigments.

Since the beginning of the 21st century, two major infectious diseases, SARS and new coronavirus pneumonia (COVID-19), have shocked China as well as the world Studies suggested bats, as well as pangolins may be the vectors of both epidemics, prompting calls for a ban on eating wild animals In fact, the country has already legislated against the consumption of legally protected and illegally sourced wild animals Market survey found no bats for sale in those markets in 16 major Chinese megacities after SARS Therefore, how did SARS-CoV and the new coronavirus COVID-19 (SARS2-CoV) spread from wild animals to humans? What lessons should we learn from these two epidemics? Besides a total ban on consumption wild animal meets from illegal source, I suggest to perfect the legislation of zoonosis and to fill the gaps in the laws concern with the prevention of zoonosis;to amend the provisions of the existing law governing the managing of zoonosis contaminated，areas A permanent institution should be set up to cover the whole process of wildlife epidemic investigation and monitoring, human-wildlife interface, quarantine, immunization of susceptible populations, popularization of law and scientific knowledge, thus to realize early prevention, early detection and early treatment of zoonosis to ensure public health security I also recommend that to establish a mechanism for the prevention and control of zoonosis, to identify wildlife hosts of zoonosis pathogens, to strengthen bat monitoring, and to issue red lines for the control of zoonosis Additionally, we shall strengthen law enforcement to prevent zoonosis;improve animal production management, marketing, and quarantine procedures I urge people to change their habit of pursuing fresh animal foods by killing animals on site in markets © 2020, Chinese Academy of Sciences All rights reserved

Neutrons are encountered in many different fields, including condensed matter physics, space exploration, nuclear power, and healthcare. Neutrons interacting with a biological target produce secondary charged particles that are damaging to human health. The most effective way to shield neutrons is to slow them to thermal energies and then capture the thermalized neutrons. These factors lead us to consider potential materials solutions for neutron shields that maximize the protection of humans while minimizing the shield mass, and which adapt well to modern additive manufacturing techniques. Using hexagonal boron nitride (hBN) as a capture medium and high-density polyethylene (HDPE) as a thermalization medium, we aim to design the optimal internal structure of h$^{10}$BN/HDPE composites by minimizing the effective dose, which is a measure of the estimated radiation damage exposure for a human. Through Monte Carlo simulations in Geant4, we find that the optimal structure reduces the effective dose up to a factor of 72x over aluminum (Al) and 4x over HDPE; this is a significant improvement in shielding effectiveness that could dramatically reduce the radiation exposure of occupational workers.

Lanthanides in the trivalent oxidation state are typically described using an ionic picture that leads to localized magnetic moments. The hierarchical energy scales associated with trivalent lanthanides produce desirable properties for e.g., molecular magnetism, quantum materials, and quantum transduction. Here, we show that this traditional ionic paradigm breaks down for praseodymium in the 4+ oxidation state. Synthetic, spectroscopic, and theoretical tools deployed on several solid-state Pr4+ oxides uncover the unusual participation of 4f orbitals in bonding and the anomalous hybridization of the 4f1 configuration with ligand valence electrons, analogous to transition metals. The resulting competition between crystal-field and spin-orbit-coupling interactions fundamentally transforms the spin-orbital magnetism of Pr4+, which departs from the Jeff =1/2 limit and resembles that of high-valent actinides. Our results show that Pr4+ ions are in a class on their own, where the hierarchy of single-ion energy scales can be tailored to explore new correlated phenomena in quantum materials., Comment: 9 pages, 4 figures, and SI (47 pages)

Gas drainage is an important method to prevent and control gas disasters. Sealing materials have an important impact on the gas drainage effect. To improve the extraction rate, the configuration and related characteristics of sealing materials were studied in this study. It was found that the fluidity increased gradually with the increase of the dosage of the suspension concentrate (SC). The water-cement ratio was directly proportional to the setting time of the slurry. Also, the mixing amount of the special cement was inversely proportional to the setting time of the slurry. The influence of the amount of foaming agent, special cement, and suspending agent on the expansion rate of the slurry was positive, and the influence gradually weakened. When the water-cement ratio of cement-based materials was 0.6, the special cement content percentage was 6, the suspension agent content percentage was 3, the plasticizer content percentage was 0.7, the early strength agent content percentage was 1.2, and the foaming agent content percentage was 0.2, the sealing effect was the best. The research results suggest that the porosity and pore length of the cement-based material are smaller than those of polyurethane, and its sealing property was better. This could further increase the sealing effect of the gas borehole, thereby facilitating gas extraction.

Coal spontaneous combustion (CSC) is a global, long-standing thermal hazard in coal mining that causes serious environmental damage, particularly in developing countries. Ionic liquids (ILs) are environmentally friendly, green, economical, and a new type of fire-preventing material that inhibits coal oxidation and alleviates thermal production. In this study, 1-butyl-3-methyl imidazole tetrafluoroborate ([BMIM][BF4]) and 1-butyl-3-methyl imidazole ([BMIM][I]) at various mass ratios (0.0, 0.5, 2.0, 5.0, and 10.0 mass%) were used to treat three types of coal (lignite, 1/3 coking coal, and anthracite) for CSC. The combustion-mass loss and thermal release rate of ILs treated relative to untreated coal samples were investigated using a synchronous thermal analyzer, and the optimal addition mass ratio of ILs was predicted. Not only do ILs have the most efficient inhibiting effect, but they also consider the economic benefit. Per thermogravimetric-differential scanning calorimetry, for the content of 5.0 mass% [BMIM][BF4], the inhibiting effect is favorable for universal applications. In addition, coal samples treated with 5.0 mass% [BMIM][BF4] were subjected to programmed-temperature heating experiment testing. The oxygen consumption rate, inhibiting effect, as well as apparent activation energy, were determined. The inhibiting effect at 120.0–150.0 °C was the most obvious, which provided the basis of the application for CSC prevention.

Herein, we present an approach to design a fluorescent molecule for detection and discrimination of fluoride-containing G series and sulfur-containing V series nerve agents. FP1 bearing two reactive groups can react with fluorides and thiols from the two types of nerve agents and generate different products with obvious and diverse fluorescences, which will be helpful when dealing with terrorist crises.

To investigate the phylogenetic status of badgers (Meles sp.) in the Qinghai Lake area and to estimate the divergence time within Eurasian badgers, the cytochrome b gene and the partial control region (CR) of mitochondrial DNA were examined as genetic markers. Our results indicated that Meles is divided into four species. Twenty one haplotypes were identified in 23 combined sequences (1,652 bp) of Cyt b and CR sequences. Results showed that Eurasian badgers were clearly divided into two major lineages: one of Western lineage, composed of badgers from Europe and Southwest Asia, and the other of Eastern lineage, composed of badgers from North and East Asia (including Japan). Furthermore, the Bayesian tree and the haplotype network indicated that the badgers in the Qinghai Lake area are Asian badgers (M. leucurus). The estimated divergence time was consistent with palaeontological evidence. The first split between the Western lineage and Eastern lineage occurred approximately 2.24 Ma. After the separation, the Southwest Asia clade split from Europe approximately 1.27 Ma and the Japan clade split from continental Asia approximately 0.99 Ma.

In this paper, a dynamic integrated energy efficiency model is presented as part of the efforts in implementing high energy efficiency manufacturing, which also aims to provide model support for energy fine-grain management as well as comprehensive energy efficiency performance analysis and evaluation of computer numerical control machine tools (CNCMT). An integrated energy efficiency index system is proposed for measurement of energy utilization performance of machine tools. And the dynamic energy efficiency model is established based on Discrete Event System Specification (DEVS), which can dynamically acquire the important machining information and the attribute information such as energy consumption and energy efficiency of CNCMT. And a case study of machining a tailstock spindle on CNC grinding machine tools is simulated by using Eclipse to validate the proposed model.

The borehole stress-meter was employed in this study to investigate the distribution of the side abutment stress in roadway subjected to dynamic pressure. The results demonstrate that the side abutment stress of the mining roadway reaches a peak value when the distance to the gob is 8 m and the distribution curve of the side abutment stress can be divided into three zones: stress rising zone, stress stabilizing zone, and stress decreasing zone. Further numerical investigation was carried out to study the effect of the coal mass strength, coal seam depth, immediate roof strength, and thickness on the distribution of the side abutment stress. Based on the research results, we determined the reasonable position of the mining roadway and the optimal width of the barrier pillar. The engineering application demonstrates that the retention of the barrier pillar with a width of 5 m along the gob as the haulage roadway for the next panel is feasible, which delivers favorable technological and economic benefits.

To probe how sex,age and season influence the behavior of Pere David′s deer(Elaphurus davidianus),we studied the diurnal activity time budget of the Pere David′s deer in Hubei Shishou Milu National Nature Reserve,by using a focus sampling and instantaneous recording methods.We conducted observation for six to ten days each month from Sept.2006 to Oct.2007.The result showed that Pere David′s deer have crescent activity pattern: foraged mainly at dawn and dusk and took a break at noon.They spent the most of their time resting(53.40%),followed by feeding(22.36%),moving(11.23%),alertness(5.03%),drinking(2.65%),and others(4.42%).Season and age-sex classes significantly influenced the activity time budgets.A greater proportion of time was spent resting in summer(58%) and autumn(58%).Significant difference were found in feeding,rest,alert and other activities(P0.01) except in drinking and moving(P0.05) among seasons.Only moving behavior showed an extremely significant difference(P0.01) and had no significant difference in rest(P0.05) among age-sex classes.There was an extremely significant difference between the male deer and the female deer in alert behavior(P0.01) while the adult males spent more time on alert than the adult females.Adults and the sub-adults spent more time feeding and rest,while calves spent more time moving,and less time feeding and rest.According to the results of ANOVA analysis on the diurnal activity time budget of sex-age classes at different seasons,for all age classes,extremely significant difference were found in drinking both summer and winter,in alertness both spring and summer((P0.01).Moreover,for adult and subadult groups,there were extremely significant difference in alertness both spring and winter,in moving both summer and winter(P0.01).

Macroecology is concerned with changes in biodiversity as well as the causes of these changes on large scales.Biodiversity can show changes over time and over space.Species diversity,as the determinant of biodiversity,shows spatial heterogeneity. China has high biodiversity.An increasing number of scientists are interested in the large-scale spatial variation in biodiversity within China.The natural environments in China have clear boundaries,which have influence the distributions of animals and ecosystems.According to climate type,China can be divided into three natural regions: the eastern monsoon region,the northwest arid region and the Qinghai-Tibetan Plateau region.Study of the spatial pattern of the biodiversity found in China may contribute to the understanding of large-scale patterns in biodiversity. The fauna information database(FID),founded by the Wildlife and Behavioral Ecology Research Group,Institute of Zoology,Chinese Academy of Sciences,contains information on the distribution of amphibians,reptiles,birds and mammals in China.The FID was compiled with data on species checklists of amphibians,reptiles,birds and mammals from 205 nature reserves across mainland China.They covered most parts of the country except Jiangsu Province,Taiwan,Hong Kong and Macau. In this study,we explored the spatial variation in the G-F indices of birds and mammals with geostatistical techniques.As a measure of species diversity,we computed the G-F index using data on birds and mammals in the FID.The G-F index,based on the Shannon-Wiener index,provides a standardized measure of the diversity of species of common origin and similar environmental requirements.We treated the G-F index as a regional variable and obtained semivariance models and parameters of birds and mammals individually for each of the three natural regions.Semivariograms were produced using semivariance analysis methods of GS-plus software.Using the semivariograms and model parameters,we analyzed the characteristics of the spatial variation in bird and mammal diversity in each natural region. The semivariance of the G-F index of birds was fitted with a linear model in the eastern monsoon region and the northwest arid region of China.The parameters demonstrated that species diversity of birds had a weak spatial dependence in the eastern monsoon region and the northwest arid region of China.There was no spatial correlation with pure nugget effects on the Qinghai-Tibetan Plateau,indicating that the spatial variation in bird species diversity was caused by random factors.This may be due to the high dispersal abilities of birds. The semivariance of the G-F index of mammals showed no relationship in the eastern monsoon region and had pure nugget effects in the northwest arid region.However,data of the Qinghai-Tibetan Plateau was best explained by a spherical model.The parameters revealed that spatial pattern of mammalian species diversity was random in the eastern monsoon region and in the northwest arid region but had a strong spatial dependence with a correlation spatial range of 71492—1020000 m on the Qinghai-Tibetan Plateau.This spatial pattern of avian and mammalian species diversity is likely attributable to the interaction between the particular physical environment and life history of birds and mammals.The macroscale spatial pattern of species diversity should be taken into account in the formation of conservation action plans.

Summary 1 Twelve species of large herbivores dwell on the steppes of Central Asia and the Qinghai-Tibet Plateau. Three of these species once occurred in vast herds in the three major rangeland ecosystems of the region. Populations of all species are now diminished, some reduced to a point close to extinction, mainly due to overharvesting and habitat loss. 2 The rate and effectiveness of hunting increased steadily throughout the second half of the twentieth century. Major social and economic changes that occurred across the region during the last 20 years have further accelerated the declining trend. 3 Synthesis and applications. Conservation of these species over the long-term presents a challenge, especially across the spatial scale required for the migratory and nomadic species. Immediate efforts are urgently needed while substantial numbers remain and extensive tracts of habitat are still intact.

We documented food habits of brown bear (Ursus arctos) during summer 2005 in an important calving area for Tibetan antelope (Pantholops hodgsonii) in the Kekexili Nature Reserve, Qinghai province, China. Fecal analysis (n = 83) revealed that the plateau pika (Ochotona curzoniae) was the primary prey (78% occurrence, 46% dry weight), and that wild yak (Bos grunniens; 39%, 31%) and Tibetan antelope (35%, 17%) were important alternative prey. Vegetation also occurred in bear feces (17% occurrence). Brown bears in this region were evidently primarily carnivorous, a survival tactic adapted to the special environment of Qinghai–Tibetan plateau.

Heavy metals pollution in Jiaozhou Bay was studied inRuditapes. philippinarum, a bioindicator of seawater pollution. Heavy metals in soda industry wastes “white mud” were also studied. Comparison of microwave digestion method with general digestion method revealed that microwave digestion is superior to general digestion in precision, recovery, digestion speed and efficiency, etc. Cd concentration in HongdaoR. philippinarum samples exceeded the national standard by 0.046 mg/kg, that of Yinghai sample by 0.02 mg/kg, and that of Hongshiya sample by 0.22 mg/kg. Sample Pb concentration in Hongshiya was found to exceed the national standard by 0.02 mg/kg. However the heavy metals concentration inR. philippinarum near the Qingdao Alkaline Factory was complied with the standard. This was proved byPenaeus chinensis culture experiment. Therefore, the possible contamination source may come from other land areas.

Li Chunwang, Jiang Zhigang, Zeng Yan & Yan CaieGraduate School of theChinese Academy of Sciences, Beijing, ChinaAbstractWe conducted an experiment in the Beijing Milu Park to study the socialbehavior of male Pe`re David’s deer, and related social behavior to socialposition and serum testosterone level of the stags during rut. We classified thestags into three rank classes according to their rutting behavior: harem master,challenger and bachelor. We monitored the behaviors of four harem masters,five challengers and five bachelors, and analyzed serum testosterone levels inblood samples of those 14 stags using radioimmunoassay. We defined theeffectiveness value, E ¼ A/T, to assess the effectiveness of herding or matingattempts made by stags (T represents the frequency of herding ormating attempts made by a stag and A represents the frequency of herdingor mating attempts accepted by hinds). We found that: (1) the harem mastersand the challengers displayed more frequent rut and locomotive behaviors butfewer ingestion behaviors than the bachelors; (2) serum testosterone levels inthe harem masters and the challengers were higher than that in the bachelors;(3) effectiveness value of herding attempts differed significantly between the threetypes of stags, being highest in the harem masters and the lowest in thebachelors; and (4) effectiveness value of mating attempts was significantlygreater for the harem masters than for the challengers. We conclude that: (1)reproductive behavior of the Pe`re David’s deer stags is strongly associated withsocial rank; (2) social roles of Pe`re David’s deer stags during the rut are relatedto the testosterone secretion; and (3) rank class affects the mating opportunity ofthe stags.Correspondence: Jiang Zhigang PhD,Graduate School ofthe ChineseAcademy of Sciences, Beijing 100080, China. E-mail: jiangzg@panda.ioz.ac.cnIntroductionMost ungulates, such as red deer (Cervus elaphus), white-tailed deer(Odocoileus virginianus), pudu (Pudu puda), antelope and domestic horse, breedby establishing a hierarchical system (Clutton-Brock et al. 1982; Gosling 1986

Cooling system is one of the key components in data centers and consumes nearly half of the total energy. For the safety and efficiency of a data enter, cooling system should guarantee all the servers running in a suitable temperature. Thus, the cooling efficiency becomes lower as the occurrence of hot spots, because the whole cooling system will accordingly work in a strong cooling mode, which leads to overcooling. One of the key challenges toward this problem is to build an effective and efficient online task scheduling to balance the inlet temperature of the servers in a data enter. In this paper, we investigate the thermal model in a data enter, and we formulate the task placement problem to an optimization problem with the purpose to minimize the maximum inlet temperature of all servers. To get higher accuracy, we proposed a dynamic thermal model updated with the real data from temperature sensors. We solve the formulated problem in an approximate way and design a first-fit decreasing task placement algorithm with the idea of CPU budget. Finally, the effectiveness and accuracy of our algorithm are confirmed by experiments on a real test bed.

A simple discrete time two-phenotype matrix game model is investigated. In this model, according to the suggestion of Vincent & Fisher (1988, Evolutionary Ecology 2, 321-337), the fitness of an individual is defined to be an exponential function of its expected pay-off value. The results show that : (i) in our model, the static conditions of ESS are only dependent on the properties of pay-off matrix, but not on the specific form of fitness function. This result implies that the ESS conditions on our model are completely identical with the conditions in the two-phenotype model with linear fitness function. (ii) In our model, the relationship between the static conditions of ESS and the dynamic properties of the pure strategy model is that if the interior fixed point of the pure strategy model is not an ESS-equilibrium, then it must be unstable; conversely, if the interior fixed point of the pure strategy model is an ESS-equilibrium, then it can be stable or unstable, and an unstable ESS-equilibrium must correspond to the cyclic or chaotic behaviour of the population state.

The leaky bucket algorithm with loss priorities is studied in this paper. The analytical expression of the relation among leaky bucket performance, statistical parameters of input traffic and leaky bucket parameters for various priority services is obtained, and the effect of adjustment factor on leaky bucket performance of higher-priority service and lower-priority service is studied with two priority classes.

There are six antelope species live or once lived in China. They mainly occupy steppes, alpine meadows, grasslands and desert shrub-lands in north and northwest China. Among them, the saiga is pronounced extirpated in wild of the country, the Przewalski’s gazelle is now critically endangered. Mongolian gazelle and Tibetan antelope were once important game species, now their distributions are greatly reduced.

The differential resistance of submicron-size ferromagnet/superconductor interface structures shows asymmetries as a function of the current through the ferromagnet/superconductor interface. These asymmetries are a consequence of spin-polarized electron transport from the ferromagnet to the superconductor, coupled with the Zeeman-splitting of the superconducting quasiparticle density of states. They are sensitive to the orientation of the magnetization of the ferromagnet, as the magnetic field required to spin-split the quasiparticle density of states can be provided by the ferromagnetic element itself., Comment: to appear in the proceedings of the St. Petersburg NATO Conference on Quantum transport, St. Petersburg, August, 2003