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POCl_3处理对Zein溶液的黏度及Zein膜的表面/机械性质的影响(英文) 被引量:2
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作者 吴磊燕 温其标 +5 位作者 杨晓泉 齐军茹 ijaz ahmad 徐明生 朱建华 胡飞 《陕西科技大学学报(自然科学版)》 2009年第3期23-31,共9页
将一种新的化学改性方法用于改变玉米醇溶蛋白(Zein)膜的性质,着重研究了Zein成膜液的黏度和Zein膜的表面/机械性质.结果表明:Zein溶液磷酸化后黏度明显增加,pH值不同,增加的程度也不相同,pH7和pH9时磷酸化的溶液黏度变化大;改性Zein膜... 将一种新的化学改性方法用于改变玉米醇溶蛋白(Zein)膜的性质,着重研究了Zein成膜液的黏度和Zein膜的表面/机械性质.结果表明:Zein溶液磷酸化后黏度明显增加,pH值不同,增加的程度也不相同,pH7和pH9时磷酸化的溶液黏度变化大;改性Zein膜的原子力显微镜(AFM)图显示石头样结构,与未改性膜相比,粗糙度(Rq)更高;除pH7的改性膜外(背面水接触角81°),其他磷酸化膜的表观接触角略微降低;Zein膜在磷酸处理后,与没改性膜相比,各磷酸化膜的抗拉强度(TS)降低,延伸率(EB)则增大,尤其是pH7和pH9时的改性膜,EB值急剧上升至150.17%和122.72%. 展开更多
关键词 玉米醇溶蛋白膜 磷酸化 接触角 表面性质 机械性质
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Lithological mapping with multispectral data–setup and application of a spectral database for rocks in the Balakot area, Northern Pakistan
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作者 Michael FUCHS Adnan A.AWAN +4 位作者 Sardar S.AKHTAR ijaz ahmad Simon SADIQ Asif RAZZAK Naghmah HAIDER 《Journal of Mountain Science》 SCIE CSCD 2017年第5期948-963,共16页
In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan... In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan spectral library(pklib) version 0.1, contains the analysis data of sixty rock samples taken in the Balakot region in Northern Pakistan.The spectral library is implemented as SQLite database. Structure and naming are inspired by the convention system of the ASTER Spectral Library. Usability, application and benefit of the pklib were evaluated and depicted taking two approaches, the multivariate and the spectral based. The spectral information were used to create indices. The indices were applied to Landsat and ASTER data tosupportthespatial delineation of outcropping rock sequences instratigraphic formations. The application of the indices introduced in this paper helps to identify spots where specific lithological characteristics occur. Especially in areas with sparse or missing detailed geological mapping, the spectral discrimination via remote sensing data can speed up the survey. The library can be used not only to support the improvement of factor maps for landslide susceptibility analysis, but also to provide a geoscientific basisto further analyze the lithological spotin numerous regions in the Hindu Kush. 展开更多
关键词 Lithological mapping Multispectral data Spectral library Normalized difference index Northern Pakistan
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Determination and inheritance of phytic acid as marker in diverse genetic group of bread wheat
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作者 ijaz ahmad Fida Mohammad +4 位作者 Aurang Zeb ijaz Rasool Noorka   Farhatullah Sultan Akber Jadoon 《American Journal of Molecular Biology》 2013年第3期158-164,共7页
Phytic acid (Myo-inositol 1,2,3,4,5,6 hexa-kisphophate) is a storage form of phosphorus and can accumulate to the levels as high as 35% in the wheat kernel. Phytic acid acts as an inhibitor for macronutrients as well ... Phytic acid (Myo-inositol 1,2,3,4,5,6 hexa-kisphophate) is a storage form of phosphorus and can accumulate to the levels as high as 35% in the wheat kernel. Phytic acid acts as an inhibitor for macronutrients as well as micronutrients and located in the bran of wheat kernel. Due to its inhibitory role, a high concentration of phytic acid is undesirable as it hinders the bio-availability of some essential nutrients such as Fe, Mg, Ca, Zn and Cu, etc. In order to check the inheritance of phytic acid in wheat kernels, phytic acid concentration was initially determined in kernels of 10 wheat genotypes to identify two contrasting genetic groups for diallel analysis. Based on pre-screening results of 10 wheat genotypes, five wheat genotypes (3 with high and 2 with low phytic acid concentration) were crossed in all possible combinations during 2007-2008 by 5 × 5 full diallel mating fashion to insight the inheritance of phytic acid and other yield contributing traits. All 20 F1 hybrids and five parental genotypes revealed significant differences statistically, except plant maturity. The narrow and broad sense heritability estimates varied widely among traits for spike length (0.17, 0.62), spikelets spike-1 (0.35, 0.74), tillers plant-1 (0.05, 0.52) and phytic acid concentration (0.01, 0.86). The values for phytic acid concentration ranged from 0.56% to 3.43% among F1 hybrids and 1.06 to 3.67% for parental genotypes. F1 hybrids, Ps-2005 × Ghaznavi (0.56%), AUP-4006 × Ps-2004 (0.74%), Janbaz × Ps-2004 (0.89%) and Janbaz × Ps-2005 (1.01%), had the lowest concentration of phytic acid. The study concluded that F1 hybrids with low phytic acid concentration could yield desirable segregants. 展开更多
关键词 Phytic Acid DIALLEL Analysis INHERITANCE HERITABILITY Yield TRAITS
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Privacy and security federated reference architecture for Internet of Things 被引量:2
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作者 Musab KAMAL Imran RASHID +3 位作者 Waseem IQBAL Muhammad Haroon SIDDIQUI Sohaib KHAN ijaz ahmad 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第4期481-508,共28页
Physical objects are getting connected to the Internet at an exceptional rate,making the idea of the Internet of Things(IoT)a reality.The IoT ecosystem is evident everywhere in the form of smart homes,health care syst... Physical objects are getting connected to the Internet at an exceptional rate,making the idea of the Internet of Things(IoT)a reality.The IoT ecosystem is evident everywhere in the form of smart homes,health care systems,wearables,connected vehicles,and industries.This has given rise to risks associated with the privacy and security of systems.Security issues and cyber attacks on IoT devices may potentially hinder the growth of IoT products due to deficiencies in the architecture.To counter these issues,we need to implement privacy and security right from the building blocks of IoT.The IoT architecture has evolved over the years,improving the stack of architecture with new solutions such as scalability,management,interoperability,and extensibility.This emphasizes the need to standardize and organize the IoT reference architecture in federation with privacy and security concerns.In this study,we examine and analyze 12 existing IoT reference architectures to identify their shortcomings on the basis of the requirements addressed in the standards.We propose an architecture,the privacy-federated IoT security reference architecture(PF-IoT-SRA),which interprets all the involved privacy metrics and counters major threats and attacks in the IoT communication environment.It is a step toward the standardization of the domain architecture.We effectively validate our proposed reference architecture using the architecture trade-off analysis method(ATAM),an industry-recognized scenario-based approach. 展开更多
关键词 Architecturally significant requirement(ASR) Architecture trade-off analysis method(ATAM) Internet architecture board Internet of Things(IoT) Privacy enhancing technologies Privacy validation chain
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煤炭腐植酸作为土壤改良剂对土壤物理性质和小麦产量的影响 被引量:10
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作者 ijaz ahmad Safdar Ali +4 位作者 Khalid Saifullah Khan Fayyazul Hassan Kashif Bashir 何一通 孙志梅 《腐植酸》 2016年第3期26-32,共7页
在巴基斯坦旁遮普的波特瓦地区(33°N,74°E),集约化土壤耕作,土壤侵蚀和低量作物残体的投入是导致土壤结构退化的原因。结构不稳定的土壤很容易受到侵蚀,反过来,土壤侵蚀又会造成作物产量的下降。因此,为了改善土壤的物理性状... 在巴基斯坦旁遮普的波特瓦地区(33°N,74°E),集约化土壤耕作,土壤侵蚀和低量作物残体的投入是导致土壤结构退化的原因。结构不稳定的土壤很容易受到侵蚀,反过来,土壤侵蚀又会造成作物产量的下降。因此,为了改善土壤的物理性状,在巴基斯坦旁遮普的干旱地区进行了田间试验。试验地点位于大学(拉瓦尔品第PMAS干旱农业大学)研究农场的园区内。2种不同等级(实验室级和商品级)的腐植酸(HA)各分8个水平,施用2年,处理分别为HL_0(对照,不施腐植酸),HL_1 10 kg HA/hm^2,HL_2 20 kg HA/hm^2,HL_3 30 kg HA/hm^2,HL_4 60 kg HA/hm^2,HL_5 90 kg HA/hm^2,HL_6 120 kg HA/hm^2和HL_7 150 kg HA/hm^2,各处理同时配合施用N-P-K(120-90-60 kg/hm^2)。试验期间,检测土壤总有机碳、饱和导水率、团聚体稳定性、容重、土壤含水量和作物产量。试验结果表明,腐植酸能通过影响土壤总有机碳、饱和导水率、团聚体稳定性、容重和土壤含水量等指标来改善土壤的物理性状。2年试验结果均表现为,实验室级的腐植酸比商品级的腐植酸能更好地改善土壤物理性状,从而提高小麦产量。2种不同级别的腐植酸各施用水平与对照相比,差异均显著。在120 kg/hm^2和150 kg/hm^2的腐植酸施用水平下,大多数指标均显示出了相似的结果,因此,从经济角度考虑,120 k g/hm^2的腐植酸用量为最佳施用量。 展开更多
关键词 实验室级腐植酸 饱和导水率 团聚体稳定性 土壤有机碳 小麦产量
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Differentially methylated genomic fragments related with sexual dimorphism of rice pests, Sogatella furcifera 被引量:2
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作者 Mei Zhang Jia-Lin Chen +3 位作者 Shi-Ke Liang Guang-Hong Li Fang-Hai Wang ijaz ahmad 《Insect Science》 SCIE CAS CSCD 2015年第6期731-738,共8页
Sogatella furcifera (Hovarth) is a major rice pest with sexual dimorphism. The objective of the current research was to monitor differentially cytosine methylation at CCGG sequences in male and female adults of S. f... Sogatella furcifera (Hovarth) is a major rice pest with sexual dimorphism. The objective of the current research was to monitor differentially cytosine methylation at CCGG sequences in male and female adults of S. furcifera to determine the association between gene methylation and sexual phenotypes using methylation-sensitive representa- tional difference analysis. After the second subtractive hybridization, four differentially methylated DNA bands were obtained and sequenced. Ten different fragments were found. One fragment from the positive hybridization was 120 bp, and highly similar to the tram- track genes from Nasonia vitripennis. Another fragment from the reverse hybridization was 414 bp, and homologous to the 28S rRNA gene of S. furcifera with a similarity rate as high as 99%. We also discussed how DNA methylation of tramtrack and 28S rRNA genes produced effects on sexual differentiation and development. These results provide potential evidence that DNA methylation of some genes may be related to sexual phenotype variations in S.furcifera and will facilitate future studies on the epigenetic mechanisms of insect sexual dimorphism. 展开更多
关键词 cytosine methylations EPIGENETICS methylation-sensitive representationaldifference analysis rice planthopper sexual dimorphism tramtrack
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Estimation of infiltration models parameters and their comparison to simulate the onsite soil infiltration characteristics
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作者 Hafiz Umar Farid Zahid Mahmood-Khan +5 位作者 ijaz ahmad Aamir Shakoor Muhammad Naveed Anjum Muhammad Mazhar Iqbal Muhammad Mubeen Muhammad Asghar 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2019年第3期84-91,共8页
Detailed knowledge about soil characteristics and site-specific final steady infiltration rate could help to increase the irrigation water use efficiency and decrease water losses in agricultural system.The experiment... Detailed knowledge about soil characteristics and site-specific final steady infiltration rate could help to increase the irrigation water use efficiency and decrease water losses in agricultural system.The experiments were conducted on Agricultural Research Farm of Bahauddin Zakariya University,Multan,Pakistan during 2016.The cumulative infiltration depth was measured using double ring infiltrometer at selected six points of the study area.Most commonly used infiltration models such as Kostikov’s,Philip’s and Horton’s were fitted to the field infiltration data for determination of model parameters and to find the best fit model for the study area.Kostikov’s infiltration model’s parameters such as empirical constant‘c’and infiltration decay constants‘k’were obtained in the ranges of 0.140-0.290 and 0.307-0.433,respectively.Philip’s infiltration model’s parameters such as sorptivity‘S’and conductivity constant‘A’were found in the ranges of 0.167-0.288 cm/min1/2 and-0.001 to-0.009 cm/min,respectively.Similarly,the Horton’s model’s‘parameter‘k’was obtained in the range of-1.619 to-1.238.The value of infiltration capacity at onset of infiltration(fo)was obtained as 1.744 to 3.491 for all the six points.The analysis showed that the infiltration models using the estimated parameters have satisfactory prediction capability at all the selected points.Horton’s model provided the lowest mean values for RMSE(0.235)and highest mean values for ME(94%);and the lowest mean values for MPD(0.127).This indicated that infiltration can be well-described by the Horton’s model at the selected site. 展开更多
关键词 infiltration characteristics infiltration models parameters estimation perdition capability
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