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In view of the new characteristics and demands presented in the actual combat training assessment of our troops in recent years, such as fast attack of weapons and ammunitions, wide attack range, multi-bomb attack multi-target, low missing test rate, giving the assessment results quickly, etc., the disadvantages of the current attack effectiveness and evaluation system are analyzed. In this paper, multi-aperture integration optical measuring station, radar and unmanned aerial vehicle (UAV) three-dimensional measurement technology, higher adaptive broadband transmission technology, measurement and control network based on cloud computing technology are explored. The aim is to promote the current single projectile effectiveness test system to multi-weapon combat effectiveness test and evaluation system, which will improve the training level of our troops rapidly.

We present numerical modeling and experiments on the THz electromagnetic signatures of various opioid powders.

A kind of nanoporous thermal insulating material was applied in torpedo ladle to reduce the heat loss of molten iron during long term transportation in this paper. The nanoporous thermal insulating material with low thermal conductivity was prepared in the laboratory. In addition, a mathematical model based on simplified physics, material properties and heat balance of actual spot data was established to predict heat loss and temperature variation of molten iron during transport. The mathematical simulation results prove that the application of a thin insulation lining can significantly improve the thermal performance of the torpedo ladle.

The present study aimed to investigate the effect of silage type on dry matter (DM) intake, nutrient digestibility, energy utilisation and methane (CH4) emission. Six late lactating Holstein dairy cows were used in a replicated 3 × 3 Latin square design study with three treatments (grass silage (GS), maize silage (MS) and whole-crop wheat silage (WCWS)) and three periods (3 weeks/period). All animals were offered forage ad libitum and 5.55 kg/day of a concentrate supplement, which contained (DM basis) 66.0% rapeseed meal, 28.3% soyabean meal and 5.7% a mineral/vitamin supplement. During each period, animals were subject to digestibility, CH4 and heat production measurements during the final 6 days using calorimeter chambers. The results demonstrated that total DM intake for MS and WCWS diets were higher (P < 0.001) than for the GS diet. Faecal energy and heat production loss for the GS diet were lower (P < 0.01) than for MS and WCWS diets. In contrast, cows fed the GS diet had higher (P < 0.05) urine energy loss compared with MS and WCWS diets. In comparison with the GS and MS diets, WCWS diet produced a lower CH4 loss per kg DM and organic matter intake (P < 0.01), and CH4 energy output as a proportion of gross energy and metabolisable energy intake (P < 0.05). The present study demonstrates that choice of forage types affects energy utilisation and CH4 emission in dairy cows.

Campoletis chlorideae Uchida (Hym., Ichneumonidae) is an important solitary koinobiont larval endoparasitoid of many noctuid species including Mythmna separata (Lep., Noctuidae). In the present study, maize volatiles induced by feeding damage of M. separata were found to be attractive to C. chlorideae in a Y-tube olfactometer. Eleven compounds were released in significant amounts from M. separata-infested maize seedlings, of which five compounds, (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, (E)-2-hexenal, linalool and phenylethyl acetate were chosen for electrophysiological and behavioural tests. All five compounds elicited electroantennogram responses in C. chlorideae. However, only pure (Z)-3-hexenyl acetate and linalool were attractive to the parasitoid in the Y-tube. Interestingly, linalool was also attractive to starved parasitoids over a range of doses tested. These results suggested that (Z)-3-hexenyl acetate and linalool may be key infochemicals in the host-foraging behaviour of C. chlorideae, and linalool may act as a food-source signal for the parasitoid.

Three point bending (3PB) tests of precracked specimens were carried out for coarse grain C–Mn steel at three low temperatures. Details of fracture surfaces in the specimens were microscopically observed and cleavage initiation sites were located. Calculations of local critical parameters and simulations of fracture behavior were made using finite element method (FEM). The results reveal that at very low temperature (−196 °C), the critical event controlling cleavage fracture is the nucleation of crack at the precrack tip in ferrite. The critical event moves to the initiation and propagation of a second phase particle crack at moderately low temperature (−110 °C). At higher temperature (−30 °C), the critical event for cleavage fracture after a fibrous crack extends is the propagation of a grain-sized crack.

The present work investigates problems: (1) How are the plastic strain and the stress (triaxiality) re-distributed after a short crack initiated, extended and blunted at the pre-crack tip? (2) How do the above changes put a crucial effect on the triggering of the cleavage fracture? Based on the previous observations of configuration changes and fracture surfaces of pre-crack tips, Finite element method (FEM) simulations of a short crack initiated, extended and blunted at a pre-crack tip and calculations of distributions of stress, strain and triaxiality are carried out for 3PB pre-cracked HSLA steel specimens tested at -130°C. The results reveal that: as long as the fatigue pre-crack is only blunted, in its vicinity a region where the accumulated strain is sufficient to nucleate a crack, and a region where the stress (triaxiality) is sufficient to propagate a crack nucleus are separated by a distance. The nucleated crack cannot be propagated and the cleavage fracture cannot be triggered. While a short crack produced at the fully blunted fatigue pre-crack, the strain retains, the stress (triaxiality) is rebuilt. An initiated and significantly extended and then blunted short crack makes a tip configuration, which on one hand is much sharper than that of the fully blunted original pre-crack tip, on other hand is wide enough to spread its effects into the high stress covered region. This sharpened crack tip configuration re-builds a ‘sharper’ distribution of stress (triaxiality) and makes two regions metioned above closer. Finally the two regions overlap each other and a cleavage crack can be initiated and propagated at a distance ahead of the blunted fatigue pre-crack.

The spatial distribution of persistent organic pollutants (POPs) was examined in soils surrounding the Tanggu Chemical Industrial District in Tianjin, China. The concentrations of hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzenes (HCBs), and polychlorinated biphenyls (PCBs) were determined in 70 surface soils using accelerated solvent extraction and gas chromatography with electron capture detection. The results showed that the ranges of ∑HCH, ∑DDT, ΣHCB, and ∑PCB concentrations in soils were 2.1-12,549 μg kg(-1) (average, 965 μg kg(-1)), n.d.-2,033 μg kg(-1) (average, 88.4 μg kg(-1)), n.d.-1,924 μg kg(-1) (average, 349 μg kg(-1)), and n.d.-373 μg kg(-1) (average, 46.2 μg kg(-1)), respectively. Of these, HCHs were the dominant POPs, accounting for 75 % of the total organochlorine pesticide (OCP) residues. Overall, the spatial distribution of OCP concentrations showed a decreasing trend from the center of the Tanggu District to the surrounding areas. Two major pollution sources were Tianjin Dagu Chemical Co., Ltd. in the district center and the Tianjin Chemical Plant in Hangu District. In contrast, PCB concentrations were relatively high in the Haihe estuary to the east and low to the west of the study area. Component analysis of OCPs in these soils showed that they mainly came from industrial point sources. Compared with soils in other regions, soil DDT pollution was at a medium level in the Tanggu Chemical Industrial District, but associated HCH, HCB, and PCB pollution was relatively heavy. By multivariate statistical analyses, Tianjin Dagu Chemical Co., Ltd. was recognized as the main source of POPs, and soil properties were clarified to play an important role on the distribution and composition of POPs, especially the organic carbon content.

Using electron microscopy and diffraction techniques, as well as first-principles calculations, we demonstrate that as much as 35% of the total Ge atoms in the cubic phase of Ge2Sb2Te5 locate in tetrahedral environments. The Ge-vacancy interactions play a crucial stabilizing role, leading to Ge-vacancy pairs and the sharing of vacancies that clusters tetrahedral Ge into domains. The Ge2Sb2Te5 structure with coexisting octahedral and tetrahedral Ge produces optical and structural properties in good agreement with experimental data and explains the property contrast as well as the rapid transformation in this phase-change alloy.

Using electron microscopy and diffraction techniques, as well as first-principles calculations, we demonstrate that as much as 35% of the total Ge atoms in the cubic phase of Ge2Sb2Te5 locate in tetrahedral environments. The Ge-vacancy interactions play a crucial stabilizing role, leading to Ge-vacancy pairs and the sharing of vacancies that clusters tetrahedral Ge into domains. The Ge2Sb2Te5 structure with coexisting octahedral and tetrahedral Ge produces optical and structural properties in good agreement with experimental data and explains the property contrast as well as the rapid transformation in this phase-change alloy.

The internal flow of a Pelton turbine is quite complex. It is difficult to analyse the unsteady free water sheet flow in the rotating bucket owing to the lack of a sound theory. Affected by manufacturing technique and silt abrasion during the operation, the bucket surface roughness of Pelton turbine may be too great, and thereby influence unit performance. To investigate the effect of bucket roughness on Pelton turbine performance, this paper presents the numerical simulation of the interaction between the jet and the bucket in a Pelton turbine. The unsteady three-dimensional numerical simulations were performed with CFX code by using the SST turbulence model coupling the two-phase flow volume of fluid method. Different magnitude orders of bucket surface roughness were analysed and compared. Unsteady numerical results of the free water sheet flow patterns on bucket surface, torque and unit performance for each bucket surface roughness were generated. The total pressure distribution on bucket surface is used to show the free water sheet flow pattern on bucket surface. By comparing the variation of water sheet flow patterns on bucket surface with different roughness, this paper qualitatively analyses how the bucket surface roughness magnitude influences the impeding effect on free water sheet flow. Comparison of the torque variation of different bucket surface roughness highlighted the effect of the bucket surface roughness on the Pelton turbine output capacity. To further investigate the effect of bucket surface roughness on Pelton turbine performance, the relation between the relative efficiency loss rate and bucket surface roughness magnitude is quantitatively analysed. The result can be used to predict and evaluate the Pelton turbine performance.

A rabbit model of alkali burned cornea was made with 1 mol/L NaOH. On days 1, 3, 7 and 14 after the burn, changes in ultrastructure and the ruthenium red (RR) proteoglycan granules were as follows: (1) The epithelium and endothelium peeled off within day 1. In lightly burned cases, the epithelium regenerated on days 3-7; (2) The collagen fibers of corneal stroma became loose and irregular after the burn and began to recover with recovery of the cornea; (3) The RR proteoglycan granules decreased markedly after the burn, in light cases they increased on day 7 and gradually exceeded the normal amount, and then they reapproached the normal when the cornea was essentially recovered.