“毛刺”及“震痕”产生的原因及解决思路

论述了模具、铸棒、挤压工艺3个因素影响"毛刺"和"震痕"的产生及解决方法.在生产高端产品的过程中,需要各工序、各操作人员的紧密配合,总接经验,不断提高操作水平,才能达到提高成品质量、降低成本的目的.

油井多相流动电磁全息测量数据处理

大多数现有数据处理方法未充分考虑传感器测量特点。为进一步提高油井多相流动电磁测量全息成像效果,针对电磁全息测量数据误差特点,抽象出其有异于理想数据的特征。采用对"突变"和"毛刺"个别压制与整体数据平滑处理相结合的策略,形成一种电磁全息测量数据处理混合算法。处理结果表明,相比以往方法,提出的混合算法能够更大限度还原测量数据实态,从而使得重建全息流动图像具有更高精度。

Formation and Control of Drilling Burrs

In this paper, a new forming model of the feed direction burr for drilling process is presented. The feed direction burr formation is experimented and studied. The related theories are analyzed, and the influential factors of the feed direction burrs are pointed out. Furthermore, a certain number of new measures to prevent and decrease the burr in drilling process are advanced.

谈数码相机的常见缺陷

在数码相机生成的数字影像上,会出现一些传统照片中没见过的色彩伪像、光溢、"毛刺"与"勾边"、色差、数码镜头景深的变化、宽容度等质量缺陷,在使用时应该特别注意,尽量避免。

A New Species of the Genus Homidia(Collembola:Entomobryidae) from Zhejiang Province,China

A new species,Homidia unichaeta,sp.nov.from East China is described.It is characterized by colour pattern,only one posterior macrochaeta on Abd.IV,labial setae E and L1 smooth,seta pi spiny and slightly thinner and about 1.5 times as long as bs1 and bs2.The three similar species of Homidia are compared.

Description of a new species of genus Homidia(Collembola:Entomobryidae) from Fujian Province

Anew species Homidiapseudosinensis sp. nov. from southeast China is described. This new species can be easily identified by posterior Th. II with a roughly M-shaped transverse band, labial setae and chaetotaxy of Abd. IV. Illustrations and a key to species of this genus from Fujian Province are provided.

Description of a new Homidia species(Collembola: Entomobryidae) with labial chaetae expanded

Homidia triangulimacula sp. nov. is described from Tiantong National Forest Park, Zhejiang Province. It can be easily discriminated from other species of Homidia by triangular dark patch on dorsal central mesothorax, labial chaeta M replicated and labial basal and posterior labial chaetae expanded, 6＋6 macrochaetae on posterior abdominal segment IV, and middle S-chaeta posterior to macrochaeta m3 on abdominal segment V. A detailed morphological character comparison and a key to species with chaetae expanded on labium or posterior labium in Homidia are provided here.

CUTTING-DIRECTION BURR FORMATION IN ORTHOGONAL PRECISION CUTTING

The cutting burr is one of the common phenomena occurring in metal cutting.In this paper,the forming processes,main effect factors and change law of the cutting direction burr in orthogonal cutting have been studied and related theories are analyzed based on the cutting experiments.The result shows that:(1)the forming processes of cutting direction burr consist of normal cutting,flexure deformation of end surface of workpiece,plastic effect,continuous cutting and shear break separating in orthogonal cutting;(2)a new phenomenon is found that cutting direction burr is formed with the shear break separation of the chip and workpiece machined surfaces;(3)the size of cutting direction burr varies with workpiece materials,cutting parameters and geometric parameters of the cutting tool.

EVENT-DRIVEN SIMULATION OF INTEGRATE-AND-FIRE MODELS WITH SPIKE-FREQUENCY ADAPTATION

The evoked spike discharges of a neuron depend critically on the recent history of its electrical activity. A well-known example is the phenomenon of spike-frequency adaptation that is a commonly observed property of neurons. In this paper, using a leaky integrate-and-fire model that includes an adaptation current, we propose an event-driven strategy to simulate integrate-and-fire models with spike-frequency adaptation. Such approach is more precise than traditional clock-driven numerical integration approach because the timing of spikes is treated exactly. In experiments, using event-driven and clock-driven strategies we simulated the adaptation time course of single neuron and the random network with spike-timing dependent plasticity, the results indicate that （1） the temporal precision of spiking events impacts on neuronal dynamics of single as well as network in the different simulation strategies and （2） the simulation time in the event-driven simulation strategies. scales linearly with the total number of spiking events

Description of a new species and the first instar larvae of Homidia(Collembola:Entomobryidae) from Taizhou,Zhejiang Province

A new species with four macrochaetae in the ＂eyebrow＂ of the anterior dorsal abdominal segment Ⅳ （Abd.Ⅳ）, Homidia quadriseta Pan sp. nov. is described fi＇om Zhejiang Province, eastern China. It can be discriminated from other recorded species in this genus by entire Abd. Ⅲ and posterior half Abd. IV darkly pigmented, 1 macrochaetae on medial Abd. Ⅲ, 2＋2 macrochaetae in ＂eyebrow＂ on anterior Abd. Ⅳ and 3 macrochaetae on posterior central Abd. Ⅳ, clypens with 12 chaetae, and fewer dental spines （7-8） on basal internal denes and with most spines slightly ciliated. Also, the chaetotaxy of the first instar of this new species is provided here.

The Evolution of Stinging Hairs and Other Characters in Nettle Family

Urticaceae Juss.is a large cosmopolitan family and taxonomically difficult group,partly because it encompasses a broad range of morphological diversity and many of the diagnostic characters（e.g.flower,achene.stipule,bract）require a microscope for accurate determination.Meanwhile,most Uriiceae species have stinging hairs which make them more difficult to collect and identify.As a result,the infra-familial classification of Urticaceae has been controversial for more than a century.A research group led by Prof.

TWENTY-THREE CASES OF ATROPHIC RHINITIS TREATED BY DEEP PUNCTURE AT THREE POINTS IN THE NASAL REGION

Atrophic rhinitis is a disease which manifests itself mainly by anosmia due to dryness and atrophy of the nasal mucosa. There is no specific therapy for the disease at present. In the past few years, 23 cases of atrophic rhinitis were treated mainly by deep puncture at three points in the nasal region with satisfactory results. In order to find out the functional changes of the nasal mucosa, the mucociliary transport rate (MTR), surface temperature of the conchal mucosa, acid-base scale of nasal secretion, and volume of nasal secretion were determined before and after the treatment.

制导武器气动舵机数学建模及故障模式仿真

为提升舵机的执行精度,根据一种出口型的制导武器气动舵机工作原理建立舵机放大器、射流管阀、作动筒、反馈电位计等关键部件的数学模型。基于所建立的数学模型进行Matlab/Simulink仿真,验证该模型在频域特性及时域特性的准确性;针对制导弹药靶试过程中气动舵机出现的“毛刺”干扰问题,分别对舵机各关键部件数学模型注入“毛刺”干扰仿真,并与制导弹药靶试遥测数据进行对比分析。仿真结果表明:气动舵机反馈电位计故障可导致气动舵机出现“毛刺”问题,经实际排除后再次靶试“毛刺”干扰得到消除,为后续制导武器气动舵机故障模式分析提供了一定理论基础。

Clinical study on skin needling plus heat-sensitive moxibustion for chronic facial paralysis

Objective：To observe the clinical efficacy of skin needling plus heat-sensitive moxibustion in treating chronic facial paralysis. Methods：Sixty patients with chronic facial paralysis were divided into an observation group and an acupuncture group by using the random number table, 30 in each group. Patients in the observation group were given skin needling plus heat-sensitive moxibustion; while patients in the acupuncture group were given conventional acupuncture. Results：Three treatment courses later, the total effective rate was 93.3% in the observation group versus 86.7% in the control group, and the difference was statistically significant （P〈0.05）. Conclusion：Skin needling plus heat-sensitive moxibustion can produce a more significant efficacy than conventional acupuncture in treating chronic facial paralysis.

Comparing twist-drill drainage with burr hole drainage for chronic subdural hematoma

Objective： of chronic subdural hematoma The surgical management （CSDH） is still a controversial issue, and a standard therapy has not been established because of the unclear pathogenic mechanisms in CSDH. The intention of this paper is to find a simple and efficient surgical procedure for CSDH. Methods： A retrospective study of 448 patients with CSDH by surgical treatment during 2005 to 2009 was conducted in order to compare the efficiency between two diferent primary surgical methods, i.e. twist-drill drainage without irrigation in Group A （n-178） and one burr-hole with irrigation in Group B （n=270）. The results were statistically analyzed. Results： The reoperation rates in Group A and Group B were 7.9% and 11.9% respectively. The good outcome rate was 88.8% and 73.5%, the complicatiGn was 7.9% and 20.7% in Group A and Group B, respectively. Conclusions： The burr-hole drainage with irrigation of the hematoma cavity is not beneficial to the outcome and prognosis. Irrigation is not important in the surgical treatmerit for CSDH. Thus in initial treatment, twist-drill drainage without irrigation of the hematoma cavity is recommended because it is relatively safe, time-saving and cost-effective.

Symbionts in Mucuna pruriens stimulate plant performance through nitrogen fixation and improved phosphorus acquisition

Aims South Africa is mainly dominated by savanna and grasslands ecosystems which have been previously reported to be acidic and nutrient deficient,specifically with regard to phosphorus(P)and nitrogen(N).Mucuna pruriens(L.)DC,commonly known as velvet bean,is an indigenous legume in most African countries and has been reported to withstand these adverse soil conditions.The legume is used in many countries of the world for their medicinal value as well as for soil fertilization purposes.Although there are reports on M.pruriens growth and establishment in nutrient stressed ecosystems,no investigation has been conducted on M.pruriens symbiotic interactions,N source preference and associated growth carbon costs when subjected to P deficiency.In this study,we determined the impact of microbial symbionts on N nutrition and growth carbon costs of M.pruriens under P deficiency.Methods Microbe inoculation soils were collected from four geographical distinct KwaZulu-Natal locations.Thereafter,seeds were germinated in these natural soils and in early stages of nodule development,then seedlings were transferred in sterile quartz sand and supplied with Long Ashton nutrient media with varying P concentrations.Important Findings The 16S RNA sequence results revealed that M.pruriens was nodulated by Burkholderia sp.,Paenibacillus sp.and Bacillus irrespective of P concentrations.Even though P deficiency resulted in decreased overall biomass/growth,the root biomass,nodule number and carbon costs increased.In addition,low P supplied saplings showed the highest arbuscular mycorrhiza fungi percentage root colonization.In M.pruriens,nitrogen derived from atmosphere had a positive correlation with P level and the saplings had a dual reliance on atmospheric derived N and soil derived N with increased reliance on soil N in low P supplied plants.Therefore,M.pruriens exhibited different morphological and microbial symbiosis when subjected to P deficiency.

Mechanosensation of osteocyte with collagen hillocks and primary cilia under pressure and electric field stimulation

Mechanosensors are the most important organelles for osteocytes to perceive the changes of surrounding mechanical environment.To evaluate the biomechanical effectiveness of collagen hillock,cell process and primary·cilium in lacunar-canalicular system(LCS),we developed pressure-electricity-structure interaction models by using the COMSOL Multiphysics software to characterize the deformation of collagen hillocks-and primary cilium-based mechanosensors in osteocyte under fluid flow and electric field stimulation.And mechanical signals(pore pressure,fluid velocity,stress,deformation)were analyzed in LCS.The effects of changes in the elastic modulus of collagen hillocks,the number and location of cell processes,the length and location of primary cilia on the mechanosensitivity and the overall poroelastic responses of osteocytes were studied.These models predict that the presence of primary cilium and collagen hillocks resulted in significant stress amplifications(one and two orders of magnitude larger than osteocyte body)on the osteocyte.The growth of cell process along the long axis could stimulate osteocyte to a higher level than along the short axis.The Mises stress of the basal body of primary cilia near the top of osteocyte is 8 Pa greater than that near the bottom.However,the presence of collagen hillocks and primary cilium does not affect the mechanical signal of the whole osteocyte body.The established model can be used for studying the mechanism of bone mechanotransduction at the multiscale level.