巴西巨人金直间捕鸟蛛的人工饲养方法

本文简要介绍了巴西巨人金直间捕鸟蛛的人工饲养过程,包括它的形态特征、生活习性、饲养器具和生长过程等,并分析了巴西巨人金直间捕鸟蛛培养过程中应注意的一些问题。

时间捕手

好莱坞电影总是带着奇幻而来,福克斯出品的电影《时间规划局》将故事设定在一个可变更时间维度的未来。在这里,时间是流通货币,每个人的生命被类似银行这样的机构存储、追踪和记录着。当预设的25岁寿命来临,每个人都必须通过工作、买卖、借贷等手段赚取时间来延续生命。电影在真爱的主题之下,反讽了现实社会存在的贫富差距,也让我们稍稍做了一场改变时间的美梦。指缝太宽,时间太瘦。制作一年规划的情景似乎还在昨日,现在却已接近回顾和盘点的年末。对于时间的哲学思辨由来已久,富兰克林最早提出了＂时间就是金钱＂的论断,寓意着耗费越少的时间将赢取越多的财富。以深圳速度来譬喻,就是＂时间就是金钱,效率就是生命＂。

溶剂捕粕新工艺

目前,我省各油厂浸出车间蒸烘机的湿式捕集器都使用冷水捕粕,废水量大(如蓬菜油厂浸出车间捕粕水量达70~80吨/日),废水温度较高(一般30°~45℃),废水中粕末的乳化作用等因素给我们杜绝从废水中损耗溶剂带来困难。 针对以上情况,我们参考日本的“溶剂捕粕”和“汽体接触塔”等工艺和设备,综合其优点,提出溶剂捕粕新的工艺方案,在本省宣汉县榨油厂新建浸出车间设计方案中得以实施,该车间自1979年4月一次试车成功以来,生产情况一直良好,溶剂捕粕新工艺也收到了予期的效果。

The role of titanium at the interface of hematite photoanode in multisite mechanism:Reactive site or cocatalyst site?

Hematite(α-Fe_(2)O_(3))constitutes one of the most promising photoanode materials for oxygen evolution reaction(OER).Recent research on Fe_(2)O_(3) have found a fast OER rate dependence on surface hole density,suggesting a multisite reaction pathway.However,the effect of heteroatom in Fe_(2)O_(3) on the multisite mechanism is still poorly understood.Herein we synthesized Fe_(2)O_(3) on Ti substrates(Fe_(2)O_(3)/Ti)to study the oxygen intermediates of OER by light-dark electrochemical scans.We identified the Fe-OH species disappeared and Ti-OH intermediates appeared on Fe_(2)O_(3)/Ti when pH=11‒14,which significantly improved the OER performance of Fe_(2)O_(3)/Ti.Combined with the density functional theory calculations,we propose that Ti atom acts as cocatalyst site and captures proton from neighboring Fe-OH species under highly alkaline condition,thereby promoting the coupling of Fe=O and reducing the energy barrier of the non-electrochemical step.Our work provides a new insight into the role of heteroatom in OER multisite mechanism based on clarifying the reaction intermediates.

投药灭鼠反伤猫

笔者养有一猫,皮毛绚丽,黄白相间捕鼠勤快,温柔可人,不料一日回家,昏迷在地,呕吐不止,遂送医急救。过了几天,猫总算大难不死,不料精神一反常态,碰到老鼠时往日的虎虎神威荡然无存,反而望鼠生畏,不敢再度问津,现出了"猫怕老鼠"的反常景观。原来这是猫吃了毒死的老鼠后的表现。老鼠的繁衍能力惊人。一只成年老鼠,年产5—10胎,每胎多只。幼鼠出世3个月又可产仔,子子孙孙呈几何数增殖。有人估算:一对田鼠产下的后代如能全数成活,只经四年。

合股养虾分户种稻 潜江市虾稻共作的“统分智慧”

4月20日清晨5点,＂垸长＂潘芝金、代万美一吆喝,＂合股养虾＂的10位农民来到三角尖垸田间捕虾。经过一个半小时作业,捕获了50多kg小龙虾。虾贩张老四早早等着收购,一共卖了2000元,当时就分到各人手中200元。70岁的刘宝财介绍说,今天收的虾不算多,又是星期一,价钱不算高。

Statistical evaluation of flotation and entrainment behavior of an artificial ore

The role of several parameters on gangue recovery in froth was investigated. Effects of frother type and collector dosage on flotation performance were tested at pH 10. The results were evaluated statistically by two-way analysis of variance without replicates, sample range and sample standard deviation. Hydrophilic mineral was recovered mainly by entrainment through hydrophobization of Ca＋2-activated quartz from tap-water in the presence of Na-oleate as collector; entrapment and slime coating were also proposed as recovery mechanisms in minority. Degree of gangue-entrainment in froth product increases by reduction in liberation size. The experimental results state that selectivity would be improved by increasing collector concentration and reducing the flotation time.

Effects of Spatial Noncommutativity on Energy Spectrum of a Trapped Bose-Einstein Condensate

In noncommutative space, we examine the problem of a noninteracting and harmonically trapped Bose- Einstein condensate, and derive a simple analytic expression for the effect of spatial noncommutatlvity on energy spectrum of the condensate, it indicates that the ground-state energy incorporating the spatial noncommutativity is reduced to a lower level, which depends upon the noncommutativity parameter 8. The gap between the noncommutative space and commutative one for the ground-state level of the condensate should be a signal of spatial noncommutativity.

Development of space end-effector with capabilities of misalignment tolerance and soft capture based on tendon-sheath transmission system

The essential requirements of the end-effector of large space manipulator are capabilities of misalignment tolerance and soft capture.According to these requirements,an end-effector prototype combining the tendon-sheath transmission system with steel cable snaring mechanism was manufactured.An analysis method based on the coordinate transformation and the projection of key points of the mechanical interface was proposed,and it was a guideline of the end-effector design.Furthermore,the tendon-sheath transmission system was employed in the capture subassembly to reduce the inertia of the capture mechanism and enlarge the capture space.The capabilities of misalignment tolerance and soft capture were validated through the dynamic simulation in ADAMS software.The results of the capture simulation and experiment show that the end-effector has outstanding capabilities of misalignment tolerance and soft capture.The translation misalignments in radial directions are±100 mm,and angular misalignments about pitch and yaw are±15°.

High-Sensitivity Acquisition of Ultrahigh Dynamic Direct Sequence Spread Spectrum Signals in Space Communications

According to the requirements of the high-sensitivity acquisition of Direct Sequence Spread Spectrum(DSSS) signals under ultrahigh dynamic environments in space communications, a three-dimensional joint search of the phase of Pseudo-Noise-code(PN-code),Doppler frequency and its rate-of-change is presented to achieve high sensitivity in sensing high-frequency dynamics. By eliminating the correlation peak loss caused by ultrahigh Doppler frequency and its rate-of-change offset,the proposed method improves the acquisition sensitivity by increasing the non-coherent accumulation time. The validity of the algorithm is proved by theoretical analysis and simulation results. It is shown that signals with a carrier- to-noise ratio as low as 39 dBHz can be captured with high performance when the Doppler frequency is up to ±1 MHz and its rate-of-change is up to ±200 kHz/s.

Dietary analysis of Homonota darwini (Squamata:Gekkonidae) in Northern Patagonia

Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimens were captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens were identified, and we tbund that prey consisted of six main groups： Coleoptera, Hymenoptera, Homoptera and Araneae, and the adults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as common prey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differences between males and females were evident. We tbund nine geckos with empty stomachs and six parasitized by nematodes. Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foraging success of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insect prey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidence of empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint of nocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have caused a generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambush forager, as are many other nocturnal gekkonids

Adaptive Optimal Control of Space Tether System for Payload Capture via Policy Iteration

The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure of capture mission.Due to unknown inertial parameters after capturing the payload,an adaptive optimal control based on policy iteration is developed to stabilize the uncertain dynamic system in the post-capture phase.By introducing integral reinforcement learning(IRL)scheme,the algebraic Riccati equation(ARE)can be online solved without known dynamics.To avoid computational burden from iteration equations,the online implementation of policy iteration algorithm is provided by the least-squares solution method.Finally,the effectiveness of the algorithm is validated by numerical simulations.

Modeling and simulations of orbital capture with space tether-net system

A new flexible tether-net space robotic system used to capture space debris is presented in this paper. With a mass point assumption, a dynamic model of the tether-net system was established in orbital frame by applying Lagrange Equations. In order to investigate the net in-plane trajectories after being cast, the non-controlled R-bar and V-bar captures were simulated with ignoring the out-of-plane libration, and the effect of in-plane libration on the trajectories of the capture net was demonstrated by simulation results. With an effort to damp the in-plane libration, the control scheme based on tether tension was investigated, then an integrated control scheme was proposed by introducing thrusters into the system, and the nonlinear close-loop dynamics was linearised by feedforward strategy. Simulation results show that the feedforward controller is effective for in-plane libration damping and enables the capture net to track an expected trajectory.

Femtosecond Optical Trapping of Cells:Efficiency and Viability

The femtosecond optical trapping capability and the effect of femtosecond laser pulses on cell viability were studied.The maximum lateral velocity at which the particles just failed to be trapped,together with the measured average trapping power,were used to calculate the lateral trapping force(Q-value) .The viability of the cells after femtosecond laser trapping was ascertained by vital staining.Measurement of the Q-values shows that femtosecond optical tweezers are just as effective as continuous wave optical tweezers.The experiments demonstrate that there is a critical limit for exposure time at each corresponding laser power of femtosecond optical tweezers,and femtosecond laser tweezers are safe for optical trapping at low power with short exposure time.

满儿(小说)

这年的第一场雪下得太厚了,人踩过去能埋没小腿。院子里的雪被我们清扫光了,背出去倒在门前高高的埂子下。大门外清扫出一条人行道。剩下的我们想等日头出来一晒,让自然的力量慢慢去消融。孩子们在院子里玩,一个个穿着鼓囊囊的劣质羽绒服和肥大的毛绒裤,戴着狗头一样的大暖帽,但是鼻涕还是冻出来了,在嘴唇上明晃晃吊着。我和嫂子起了一大盆面,淘洗了白萝卜和黄萝卜,切菜的切菜,煮肉的守着一口大锅烧火。热气腾腾中婆婆扭着脚跑进来,快快快,先把活儿停下,拾掇点吃头,亲戚来了!随着语声门口一暗,紧接着又亮了,婆婆走了。

Positivity and boundedness preserving schemes for the fractional reaction-difusion equation

In this paper, we design a semi-implicit scheme for the scalar time fractional reaction-diffusion equation. We theoretically prove that the numerical scheme is stable without the restriction on the ratio of the time and space stepsizes, and numerically show that the convergence orders are 1 in time and 2 in space. As a concrete model, the subdiffusive predator-prey system is discussed in detail. First, we prove that the analytical solution to the system is positive and bounded. Then, we use the provided numerical scheme to solve the subdiffusive predator-prey system, and theoretically prove and numerically verify that the numerical scheme preserves the positivity and boundedness.

PERIODIC SOLUTION AND PERSISTENCE FOR A THREE-SPECIES RATIO-DEPENDENT PREDATOR-PREY MODEL WITH TIME DELAYS IN TWO-PATCH ENVIRONMENTS

The author considers a three-species ratio-dependent predator-prey model with time delay in a two-patch environments. This model is of periodic coefficients, which incorporates the periodicity of the environment. By means of the coincidence degree theory, sufficient conditions for the existence of at least one positive periodic solution of this model are established. Moreover, The author shows that the system is uniformly persistent under the conditions.

Long-time behavior of a stochastic predator-prey model with modified Leslie-Gower and Holling-type II schemes

In this paper, we consider a stochastic predator-prey model with modified Leslie-Gower and Holling-type II schemes. We analyze long-time behavior of densities of the distri- butions of the solution. We prove that the densities can converge in L1 to an invariant density or can converge weakly to a singular measure under appropriate conditions.

Boldness and predator evasion in naturally hybridizing swordtails （Teleostei： Xiphophorus）

Correlations among behavioral traits can generate trade-offs and constrain phenotypic evolution. Interspecific hybridization has the potential to alter behavioral trait correlations, but the effect of hybridization on suites of behavioral traits has received relatively little attention. We evaluated how natural hybridization changes the relationship between boldness （time of emergence and proportion of time out of shelter） and response to a simulated predator threat in swordtails （Teleostei： Xiphophorus）. In poeciliid fishes, bold individuals have increased survival in the presence of predators. This non-intuitive observation may arise as a result of bold individuals being more likely to engage in anti-predator behaviors. Contrary to our prediction, bold indi- viduals were less likely to perform a fast-start response to a predator threat. This correlation was consistent among populations and species but was only significant in hybrids. The observed correlation between boldness and anti-predator behavior could im- pact hybrid fitness and the evolvability of hybrid lineages. More generally, our findings suggest that hybridization could influence the integration of behavioral phenotypes, as has been amply documented for morphology. Animal personality and behavioral syndromes could therefore play an important role in the evolutionary fate of natural hybrids [Current Zoology 61 （4）： 596-603, 2015].

Acquisition algorithm assisted by AGC control voltage for DSSS signals

An appropriate acquisition configuration in terms of signal quality can optimize the acquisition performance. In view of this, a new approach of acquisition assisted by the control voltage of automatic gain control(AGC) is proposed. This approach judges the signal power according to the AGC control voltage and switches the working modes correspondingly and adaptively. Non-coherent accumulation times and the detection threshold are reconfigured according to the working mode. Theoretical derivation and verification by simulation in typical situations are provided, and the algorithm is shown to be superior in terms of the mean acquisition time, especially in strong signal scenarios compared with the conventional algorithm.