Crimp analysis of worsted fabrics in the terms of fabric extension behaviour     

N. Ezaz Shahabi  F. Mousazadegan  S. M. Hosseini Varkiyani  S. Saharkhiz 《Fibers and Polymers》2014,15(6):1211-1220

Inside a woven fabric structure, warp and weft yarns acquire crimp as a result of yarns interlacing according to the weave pattern. Since warp and weft yarns are oriented in two perpendicular directions, applying tensile load in one direction causes extension in the load side and fabric contraction in the opposite direction. This process was investigated in this study by using an image processing procedure and it was found that fabric’s extension is in coincidence with yarn’s de-crimping process in the same direction. After the de-crimping stage, yarns in the load direction will be extended and at the same time crimp in the other direction will be increased, until jamming phenomenon happens in the fabric structure. The crimp interchange between warp and weft yarns follows a three-order polynomial function with a turning point in which the yarns in the load direction have no crimp.  相似文献   

Changes in δ15N in a soil–plant system under different biochar feedstocks and application rates     

Frédérique Reverchon  Robert C. Flicker  Hong Yang  Guijun Yan  Zhihong Xu  Chengrong Chen  Shahla Hosseini Bai  Dongke Zhang 《Biology and Fertility of Soils》2014,50(2):275-283

The application of biochar in soils has been hypothesised to improve soil quality whilst enhancing carbon (C) sequestration. However, its effect on nitrogen (N) dynamics in the soil–plant system is still not fully understood. In the present work, N isotope composition (δ¹⁵N) was used to facilitate the understanding of the processes involved in the N cycling when biochar is applied. We evaluated, through a wheat pot trial, the effect of different application rates of two types of biochar produced from jarrah and pine woodchips on the wheat biomass at harvest and on the soil and plant C and N contents and δ¹⁵N. In addition, the potential benefit of using nutrient-saturated biochar for the soil–plant system was also investigated. Whilst biochar produced from different feedstocks had similar effects on soil and plant nutrient contents, they induced differences in wheat grain biomass and plant δ¹⁵N. The effect of the biochar application rate was more pronounced, and at rates higher than 29 t ha^?1, the application of biochar decreased grain biomass by up to 39 % and potentially increased N losses. Isotopic analyses indicated that this acceleration of N dynamics had probably occurred before the stage of wheat grain formation. The application of nutrient-enriched biochar resulted in an improved wheat grain production, most likely due to the enhanced nutrient availability, and in reduced N cycling rates in the plant–soil system, which could offset the competition between biochar and plants for nutrients and could decrease adverse environmental impacts due to N losses.  相似文献   

Isolation and identification of anionic surfactant degrading bacteria from activated sludge     

Amirmozafari N  Malekzadeh F  Hosseini F  Ghaemi N 《Iranian Biomedical Journal》2007,11(2):81-86

BACKGROUND: Linear alkylbenzene sulfonate (LABS) is an anionic surfactant widely used all over the world. They will eventually end-up and accumulate in household or industrial sewage. Due to their high foaming capabilities which can cause numerous problems in sewage treatment facilities as well as direct toxic effects on many different organisms in ecosystem; they are generally considered as serious pollutants. Many reports have indicated that common bacteria can readily degrade LABS. METHODS: In this survey, two different bacteria were isolated from Tehran municipal active sludge that showed the ability to degrade LABS rapidly and actively upon using it as their sole source of carbon. Biochemical tests as well as 16S rRNA gene sequencing performed. RESULTS: Results have indicated the two isolates to be Acinetobacter johnsoni and Pseudomonas beteli. After experiments to optimize the pH and temperature for growth of the two bacterial isolates, the extent of LABS, utilization was evaluated by HPLC method. The Pseudomonas beteli and Acinetobacter johnsoni isolates were able to degrade 96.4% and 97.2% of the original LABS levels after 10 days of growth, respectively. Mixed culture of the two isolates did not significantly increase LABS utilization (97.6%). CONCLUSION: Our study showed the ability of two isolated steains to rapidly biodegrade LABS under aerobic conditions.  相似文献   

栽培墨兰根腐病病原鉴定与生防菌筛选     

唐婕  陈健鑫  尼玛此姆  魏玉倩  落追  韩雨庭  吕则佳  马焕成  伍建榕 《中国农学通报》2021,37(19):128-133

为明确墨兰根腐病的病原,提出绿色生防措施,以发生根腐病的墨兰为材料,采用组织分离法分离病原菌,并对其进行形态学鉴定及分子生物学鉴定,通过柯赫氏法则验证致病性。同时,采集野外健康墨兰根部和土壤,采用稀释涂布法分离获得20株细菌,通过平板对峙培养,筛选出1株细菌MJ5-1能同时拮抗2株病原真菌。通过16S rRNA基因序列分析,该拮抗菌为短小芽孢杆菌(Bacillus pumilus)。结果表明,导致云南墨江栽培墨兰根腐病的病原是腐皮镰刀菌(Fusarium solani),短小芽孢杆菌(Bacillus pumilus)MJ5-1能抑制腐皮镰刀菌菌丝及孢子的生长。研究结果可为产业化栽培墨兰的根腐病诊断及无公害防治提供理论依据。  相似文献   

Changes of extracted bioactive compounds from brown algae (Cystoseira indica) after conversion to mill and tablet using a quantitative metabolomics approach     

Fasakhodi  Maliheh Taheri  Abed-Elmdoust  Amirreza  Mirvaghefi  Alireza  Hosseini  Seyed Vali  Tavabe  Kamran Rezaei 《Aquaculture International》2021,29(6):2793-2804

Aquaculture International - There is developing importance in the biomedical use of seaweeds such as brown algae, mostly due to their contents of bioactive substances. In the present study,...  相似文献   

Morphometric study of the testis in sheep embryos using unbiased design-based stereology     

Javad Sadeghinezhad  Zahra Ganji  Sirous Sadeghian Chaleshtori  Hadis Bojarzadeh  Mahdi Aghabalazadeh Asl  Ali Bayat Khomejini  Ehsan Roominai  Mohsen Hosseini  Margherita De Silva 《Anatomia, histologia, embryologia》2021,50(6):1026-1033

Sheep have been used as translational models of human postnatal testicular development. However, the morphometric features of the normal developing testis in sheep embryos have not been previously investigated using stereology. The objective of the present work was to establish normal quantitative parameters for fetal testicular tissue components in sheep, using unbiased design-based stereological methods. Twenty-four sheep embryos were divided into four gestational age groups (9–11, 12–14, 15–17 and 18–20 weeks of gestation) on the basis of the embryos’ crown-rump length. Isotropic, systematic uniform random sections of the left testes were obtained by employing the orientator method. Testicular total volume, the absolute and proportional volumes occupied by the seminiferous tubules and interstitial tissue, as well as the seminiferous tubule length, were estimated using the point-counting system and the unbiased counting frame principle. All the parameters, with the exception of the interstitial tissue's fractional volume, gradually increased along with gestational age, with the maximum increase especially seen in the late fetal stages. The proportional volume of the interstitial tissue, on the other hand, showed a decreasing trend along with increasing gestational age. The absolute volume of the testes, of the seminiferous tubules and of the interstitial tissue, and the length of the seminiferous tubules showed a significant (p< 0.05) positive linear correlation with gestational age. Several similarities were observed with human testicular embryogenesis. The stereological data emerging from the present study might prove useful as basic contribution to the fields of andrology and embryology and stimulate further research in these areas.  相似文献   

Efficacy of conventional and extended intra-mammary treatment of persistent sub-clinical mastitis with cefquinome in lactating dairy cows   总被引：1，自引：1，他引：0  

Kasravi R  Bolourchi M  Farzaneh N  Seifi HA  Barin A  Hovareshti P  Gharagozlou F 《Tropical animal health and production》2011,43(6):1203-1210

The objectives of the present study were to evaluate the efficacy of intra-mammary-administered cefquinome for the treatment of sub-clinical mastitis in lactating dairy cows and to determine if extended therapy would enhance treatment efficacy. Seventy-three Holstein dairy cows from a single farm with 150 infected quarters were enrolled in the study. Infected cows were allocated randomly to one of three treatment regimens: (1) conventional (standard) regimen: 75 mg of cefquinome administered three times at 16-h intervals (25 infected cows, 52 intra-mammary infections (IMI)), (2) extended regimen: 75 mg of cefquinome administered six times at 16-h intervals (26 infected cows, 58 IMI) and (3) negative untreated control group (22 cows, 40 IMI). Most IMI were caused by coagulase-negative staphylococci, streptococci other than Streptococcus agalactiae and coliforms. The overall bacteriological cure (BC) rates for sub-clinical IMI were 84.61%, 91.37% and 20% for the conventional, extended and the control groups, respectively, indicating a higher BC rate for the treated groups than the control group (P < 0.001). Significant differences in somatic cell count (SCC) were detected between the treated versus the control group (P < 0.001). No differences, concerning the BC rate or SCC, were observed between the extended and the conventional groups. Although fat and protein percentages increased in the treated groups, there were no significant differences in post-treatment milk production between the groups. Results of this study indicate that cefquinome therapy was effective in reducing SCC and eliminating sub-clinical IMI in lactating dairy cows, but extended therapy did not enhance treatment efficacy.  相似文献   

Nickel supplementation effect on the growth,urease activity and urea and nitrate concentrations in lettuce supplied with different nitrogen sources     

Amir Hossein Khoshgoftarmanesh  Fatemeh Hosseini  Majid Afyuni 《Scientia Horticulturae》2011

Effect of nickel (Ni) in the nutrient solution on yield, N metabolism, and nitrate content of leafy vegetables is poorly understood. The aim of this nutrient solution culture experiment was to investigate the effects of Ni supplementation on the nitrogen (N) metabolism and growth of lettuce (Lactuca sativa L. cv. Baker) with either urea or nitrate as the N source. Nickel supplement at 0.04 μM reduced urea toxicity to the urea-fed plants. Addition of Ni to the nutrient solution significantly increased the leaves and root growth of the urea-fed lettuce plants while it increased the growth of lettuce plants fed with nitrate only at N level of 20 mM. At N level of 20 mM, the leaves fresh weight of the urea-fed plants promoted by Ni supplement was comparable with the nitrate-fed plants untreated with Ni. Nickel supplementation increased the leaf total N concentrations in the urea-fed plants, although the nitrate-fed plants accumulated greater N in their leaves compared with urea treated plants at without Ni treatment. Nickel addition decreased the concentrations of leaf urea-N in the urea-fed plants and NO₃-N in the nitrate-fed plants. Nickel addition enhanced urease activity in the leaves of urea-fed plants. The results indicated Ni supplementation enhances the growth of the urea-fed lettuce plants while it has role in decreasing leaf nitrate concentration and thus, improving the health quality of the nitrate-fed plants.  相似文献   

Effects of superabsorbent polyacrylamide hydrogel and gypsum applications on colloidal phosphorus release from agricultural soils     

Hosseini  Seyed Hamid  Niyungeko  Christophe  Khan  Sangar  Liang  Xinqiang 《Journal of Soils and Sediments》2021,21(2):925-935

Purpose

The present study aimed to assess the synergistic effects of superabsorbent polyacrylamide hydrogel (SPH) and gypsum on colloidal phosphorus (CP) release from different farmlands (i.e. tea, vegetable, and paddy soils).

Materials and methods

A laboratory experiment was carried out to examine the effects of SPH at different rates of 0.00, 0.01, 0.05, and 0.1% (w/w) and gypsum at the rates of 0 and 0.005% (w/w) on CP released from different farmland soils. For this purpose, CP, colloidal molybdate–reactive P (MRPc), and colloidal molybdenum–unreactive P (MUPc) were measured in soil solutions.

Results and discussion

The results revealed that the release of CP, MRPc, and MUPc ranged respectively from 5.20 to 56.65, 1.62 to 39.09, and 0.33 to 37.10% of total P (TP) in soil solutions across three farmland soils. Besides, the soils treated with SPH and gypsum (0.1%) mitigated CP release respectively by 51.75%, 62.64%, 24.13%, and 62.74% for tea, vegetable, silt loam paddy, and loam paddy soils. However, the MRPc release dropped respectively by 40.22%, 41.04%, 38.55%, and 63.70% in tea, vegetable, silt loam paddy, and loam paddy soils, and similar trends were observed in MUPc, namely, 43.72%, 49.37%, 35.71%, and 56.17% respectively in tea, vegetable, silt loam paddy, and loam paddy soils. The results indicated that gypsum could make a binding in the carboxyl group of polyacrylamide (PAM)/SPH and anion CP because of decreased CP release.

Conclusions

The major form of P was CP, and co-application of PAM/SPH and gypsum could be a promising management approach to moderate CP release from agricultural soils.

  相似文献   

The effects of operating parameters on the fabrication of polyacrylonitrile nanofibers in electro-centrifuge spinning     

F. Dabirian  S. A. Hosseini Ravandi  A. R. Pishevar 《Fibers and Polymers》2013,14(9):1497-1504

Introduced recently, electro centrifuge is a new method for nanofiber production. In the electro-centrifuge method, fibers are produced by the simultaneous use of electrical and centrifugal forces. In this research, the effective parameters in the production of PAN nanofibers diameter and the influence of each of them have been discussed. These parameters are voltage, rotation speed, flow rate of exiting solution from nozzle and viscosity of solution. Also the capability of fiber production by this method is compared with the conventional electrospinning system. Results show that a significant enhancement can be achieved by proper adjustments of the polymer solution viscosity, applied voltage, and rotational velocity in fiber production rate. To exemplify, in a PAN polymer solution, the increased production rate of electro centrifuge varied from 193 to 1200 percent, as compared with a similar electrospinning method in which the polymer concentration and applied voltage varied in a range of 13 to 16 wt% and 15 to 10 kV, respectively.  相似文献