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Cladophora is one of the most species-rich and taxonomically challenging taxa of green algae. Recently, some samples of freshwater filamentous algae were collected from Hubei, Yunnan and Guizhou Pr...

Researches on detecting Web spam are in full swing. However, very high feature dimension and sensitive information leakage restrict the mining. In this paper, a cascade feature selection for mining spam is proposed, which bases on Privacy Preservation (PP) method and Genetic Algorithm (GA). Two criteria, privacy protection degree and maximum classification reliability, are used to pick the representative features to form an optimal minimum feature subset. Discretization, data balancing, feature selection, and ensemble learning method are integrated to detect Web spam. The approach not only greatly reduces the data dimension but also protects the sensitive features from detection. Good spam detection performance is achieved by using only 22 features.

This study aimed to investigate the efficacy of compound probiotics on broiler performance, intestinal microflora, immune function and serum biochemical indicators. Four hundred one-d-old female broiler chickens were randomly divided into 4 groups with 4 replicates in each group and 25 chickens per replication. The chickens in groupI(control group) were fed a basal diet, experimental groups II, III and IVwere fed the basal diet supplemented with 0.1%, 0.2% and 0.4% compound probiotics. The results of this work were as follows: (1) during the experimental period, compared with control group, the average daily in group III was significantly increased (PPPE.coli has the opposite results. (3) the anti-body titer in group III was the highest, and significantly higher compared to the control (PP>0.05). (4) serum biochemical indexes of broilers in group III and IVwere significantly increased than that in control group (P

This paper describes the influence of heat treatment process on the microstructure and properties of a new martensitic stainless steel, which contains 0.7% carbon, 17% chromium and 1% molybdenum and can be used as kitchen knives and scissors. The microstructure and properties of the tested alloys after quenching at 980 - 1100 °C and low tempering were investigated by means of optical microscope (OM), scanning electron microscope (SEM), Rockwell hardness tester and impact tester. The results show that the microstructure consists of acicular martensite, carbides and a litter retained austenite after quenching and tempering. The carbides are mainly (Fe,Cr)23C6. The content of retained austenite increases with the increase of the quenching temperature. The solubility of carbon in martensite changes similarly. The martensite gets coarser as the quenching temperature increasing. The maximum value of hardness is 59 HRC, when the quenching temperature is 1060 °C. The impact toughness increases when the quenching temperature increases from 980 °C to 1080 °C and then decreases. The suitable heat treatment process for this alloy is quenching at 1060 °C~1080 °C for 30 min and then tempering at 200°C.

Effects of replacing partial zinc dust with conductive pigments on the anti-corrosion properties of ethyl silicate zinc-rich coatings with low zinc content were investigated. Salt spray test, salt immersion test and open circuit potential(OCP) measurement were utilized to evaluate anti-corrosion properties. Experimental results revealed that the effects of conductive pigments content on anti-corrosion properties are similar for di-iron phosphide powder, graphite powder and aluminum powder employed in this article. For every kind of conductive pigments, protection life in salt spray test, protection life in salt immersion test, galvanic protection life and initial OCP change with conductive pigments content increase in a similar way. They all reach an extreme point, and all the extreme points correspond to a same replacing ratio named best replacing ratio. The best replacing ratio is 20,15 and 15wt% for di-iron phosphide powder, graphite powder and aluminum powder respectively. Comparing with non-replacing coatings, conductive pigments-containing coatings at best replacing ratio possess both lower zinc content and better anti-corrosion properties.

Brine shrimps of the genus Artemia are aquatic species of economic importance because of their important significance to aquaculture and are used as a model species in physiology and developmental biology. Research on Artemia POU homeobox gene function will enhance our understanding of the physiological and developmental processes of POU homeobox gene in animals. Herein, a full-length cDNA encoding an Artemia POU homeobox protein gene 1 (APH-1) from Artemia sinica (designated as As-APH-1) was cloned and characterized by a reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE) method. The As-APH-1 gene encoded a protein of 388 amino acid polypeptide with a calculated molecular mass of 42.85kDa and an isoelectric point of 6.90 and the protein belongs to the POU III family. Multiple sequence alignments revealed that A. sinica As-APH-1 protein sequence shared a conserved POU homeobox domain with other species. The early and persistent expression of As-APH-1 in the naupliar stages by semi-quantitative RT-PCR and whole-mount embryonic immunohistochemistry suggest that As-APH-1 functions very early in the salt gland and may be required continuously in this organ. Later in development, expression of As-APH-1 begins to dramatically decrease and disappear in salt gland of the sub-adult Artemia. In addition, we also discovered that As-APH-1 increased obviously as the salinity increased, indicating that As-APH-1 might be used as a good indicator of salinity stress. In summary, we are the first to identify the As-APH-1 gene and to determine its gene expression patterns in early embryogenesis stages and in different salinity stress in brine shrimp, A. sinica. The result of expression of As-APH-1 affected by salinity changes will provide us further understanding of the underlying mechanisms of osmoregulation in Artemia early embryonic development.

For principle of the particle system, using Visual C++ combining with the object-oriented technology and open graphic library method, the shapes of oil atomization under different voltages were simulated. By comparing the simulating images with the experimental pictures, charged oil atomization process was basically reflected by the simulated results, and it was correspondent with the experimental observation.

As is known to all, a vehicle air brake system usually contains moisture. To help solve the problem, it is common to use air dryer to dry compressed air effectively and completely remove the moisture of braking system. However, the existing air dryer has many defects such as low drying efficiency, high cost, complex structure and difficult assembly. In order to solve these problems, our company began to study new Air Dryer, meanwhile, to improve the service life of air dryer.

The p8 protein is a transcription factor with a basic helix-loop-helix motif and a nuclear localization signal. In the present study, a common sea urchin (Paracentrotus lividus) homolog of p8 cDNA was cloned, sequenced and characterized. The full-length p8 cDNA consists of 896 bp and encodes 71 amino acids with a molecular mass of 8.238 kD. Homology alignments found that several phosphorylation sites and the most negative (Asp and Glu)/positive (Arg) propensities charged residues were well conserved between P. lividus and other species. Analysis by RT-PCR showed that there was no obvious difference in the patterns of expression during embryogenesis from unfertilization egg up to the pluteus stage, but p8 mRNA expression levels varied among tested adult tissues suggesting that p8 has a key function in embryogenesis but non-vital function under physiological conditions. Evolution relationships between P. lividus p8 and other species p8 homologs revealed in the phylogenetic tree were in agreement with the concept of traditional taxonomy.

Impact wear performance of the alloyed liner steels with different composition in corrosive condition was investigated. The impact energy was 1.5 J. By analyzing the worn surface morphology and the subsurface optical metallographic of the samples, the microstructure and the wear mechanism of the steels were investigated. The results show the liner steel containing 2%Ni has better impact-wear resistance than the steel containing 1%Ni and the steel without Ni. The dominant wear mechanism of the steel containing 2%Ni is the shallow fatigue flaking and slight corrosion wear. The dominant wear mechanism of the steel containing 1%Ni is the shallow fatigue flaking too, but a little heavier. The dominant wear mechanism of the steel without Ni is deep fatigue flaking. The result was useful for developing better cost-performance alloyed liner steel.

To study the volatile compounds of Salix babylonica, and to provide scientific basis for efficacy of attracting natural enemies and medicinal value of Salix babylonica.The volatile compounds were collected from Salix babylonica by dy- namic headspace absorption method, and analyzed by gas chromatography-mass spectrum( GC-MS).Forty-one volatile com- pounds were identified from Salix babylonica. Intact plant of Salix babylonica had thirty-three kinds of volatile compounds and aphid-in- fested plant of Salix babylonica had thirty-eight kinds of volatile compounds. The volatile components of intact plant and aphid-infested plant had significant differences in the composition and proportion. Among them,the volatile components of aphid-infested plant added six kinds of vinyl materials,one kind of aldehyde and one kind of ketone.Adding volatile components,which included vinyl materials,aldehydes and ketones,might have the efficacy of attracting natural enemies. The volatile components might play an important role in the ecological protection for Salix babylonica. The functional components from the volatile compounds had good medicinal value, which are worthy of further research.

To study the volatile compounds of fresh tea leaves from Yaoluoping Nature Preserve, and to provide scientific basis for the quality and medicinal value of tea from high mountainous area.The volatile compounds were extracted from fresh tea leaves by simultaneous distillation and extraction, and analyzed by gas chromatography-mass spectrum (GC-MS).41 volatile compounds were identified from two tea cultivars, Shifoxiang and Shifocui. Shifoxiang had 32 kinds of volatile compounds and Shifocui had 38 kinds of volatile compounds. The main volatile components of Shifoxiang and Shifocui were green leaf volatiles. The kind and relative content of terpenes of Shifocui were more than that of Shifoxiang. Also the kind and relative content of ketones of Shifocui were more than that of Shifoxiang. There was one kind of heterocyclic compound of Shifocui.The main volatile components of Shifoxiang and Shifocui had an important role for the formation of unique aroma of high mountain ous tea. The composition and proportion of volatile components between Shifoxiang and Shifocui had certain differences. Some trace components may be associated with defense in the process of tea plant growth. The functional components from the volatile components had good medicinal value, worthy of further research.