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51.
52.
Ma Chih-Ming Ku Young Kuo Yu-Lin Chou Yiang-Chen Jeng Fu-Tien 《Water, air, and soil pollution》2009,197(1-4):313-321
Water, Air, & Soil Pollution - The decomposition of gaseous isopropanol (IPA) by UV/TiO2 process in an annular photoreactor was studied under various conditions such as UV light intensity and... 相似文献
53.
The male sterility system in hybrid seed production can eliminate the cost of emasculation and ensure seed hybridity through
avoidance of self pollination. GMS and CMS are two types of male sterility system that currently employed in pepper breeding.
Conversion from GMS to CMS will increase the male sterility proportion of female parent from 50 to 100%. In this study, segregation
analysis of four male sterile mutants consisting of one CMS mutant (CA1) and three GMS mutants (GA1, GA3 and GA4) showed that
each had single recessive gene inheritance. A modified complementation test was performed by replacing male sterile mutants
with their maintainer line as male parent. The nuclear restorer gene for CMS was independent of all nuclear restorer genes
for GMS and all nuclear restorer genes for GMS were independent each other. Further observation on CMS and GMS male sterility
loci revealed that GA1 and GA3 had mutated in both nuclear restorer genes for CMS and GMS, while CA1 and GA4 each carried
mutation in single male sterility system of nuclear restorer gene for CMS and GMS, respectively. Conversion from GMS to CMS
in the case of lines carried mutations in both sterility systems required only S-type cytoplasm donor, while lines carried
mutation in single nuclear restorer gene for GMS required not only S-type cytoplasm but also rf allele donors. The important finding is the broader function of maintainer line in certain male sterility system that can
be used as a maintainer or restorer line for other male sterility systems. We also confirmed that line CC1 is the general
restorer for both CMS and GMS systems. 相似文献
54.
Piotr Hliwa Mamadou Bah Henryk Kuźmiński Stefan Dobosz Andrzej Ciereszko 《Aquaculture International》2014,22(1):89-96
Ultrasound approach has been used to assess morphology of the gonadal structure in the sex-reversed rainbow trout females (neomales) provided in the course of 11β-hydroxyandrostenedione treatment applied within gonadal differentiation period. Eighteen matured individuals (in range 38.0–48.6 cm of body length and 802–1644 g of body weight) were scanned using digital ultrasound apparatus (DP-6900 model) Mindray Ltd., during the spawning season. After screening, fishes were killed to validate the morphological configuration and position of the gonads in the body cavity. The favorable place for cross-sectional imaging of gonadal lobes was half of the distance between the pectoral and pelvic fins below lateral line of neomales. Most of the examined specimens (61 %) had properly shaped, paired testis. Moreover, presence of individuals with asymmetrical gonads (33 %) and one bisexual fish was confirmed. There were no differences between total volume of sampled semen and sperm motility, but statistically significantly different in sperm concentration within selected (with symmetrical and asymmetrical testis) groups of neomales. It was confirmed that ultrasonic imaging is an efficient and accurate method to determine the state of gonads of mature sex-reversed rainbow trout females during spawning season and offers the opportunity for non-invasive detection of any morphological anomalies in their gonads. 相似文献
55.
Pine (Pinus densiflora) bark was chemically modified by grafting with acrylonitrile (AN) through Fenton reaction and conversion of the cyano group
to an amidoxime group by reaction with hydroxylamine. Treatments of pine bark with 160 mM H2O2 at 40°C yielded ~70% grafting in 6-h reaction. After alkali hydrolysis of amidoximated pine bark (AOPB), its adsorption capacity
(q
e) for copper ions was largely increased from 0.5 to 1.8 mmol/g. Adsorption of the hydrolyzed AOPB (HAOPB) followed the pseudo-second-order
kinetic model. Among the metal ions tested, the order of adsorption capacity (q
e) predicted by the kinetic model at equilibrium time was Hg2+ > UO2
2+ > Cd2+ > Cu2+ > Zn2+ > Ni2+. The adsorption process was pH-dependent, and the adsorption equilibrium was observed in the pH range of 6–7 for all the
metal ions. Even though pine bark is a good adsorbent for Hg2+ and UO2
2+ ions, it had a poor affinity for the other ions tested. It was obviously found that HAOPB had very high adsorption abilities
for heavy metal and uranyl ions. 相似文献
56.
57.
以N-氨甲酰甘氨酸和七水合硫酸亚铁为原料合成了N-氨甲酰甘氨酸亚铁,并通过正交实验优化得到了最佳合成工艺条件.结果表明,当n(C3H6N2O3)∶n(FeSO4·7H2O)=2∶1时,以水为溶剂,维生素C(VC)为抗氧化剂,NaOH为pH调节剂,弱酸条件下60℃反应10 min,产品收率达到78.1%. 相似文献
58.
为加强苦菜和蒲公英的进一步开发利用,研究了乙醇浓度、料液比和提取时间对苦菜和蒲公英总黄酮得率以及不同浓度提取物对苦菜和蒲公英抗氧化活性的影响。结果表明:苦菜和蒲公英总黄酮提取的最优化条件为提取液乙醇的浓度为60%,料液比为1:30,超声提取时间为0.5h,总黄酮得率分别为6.44%和17.56%。苦菜和蒲公英提取物对DPPH自由基清除率随样品提取物浓度的增大而升高,在浓度为9.6rag·mL^-1时,苦菜和蒲公英提取物的DPPH自由基清除率都达到最大,分别为76.47%和80.39%。 相似文献
59.
1 有机微量元素的概念和分类
1.1 有机微量元素的概念
有机微量元素是指微量元素的无机盐与有机配位体形成产物的总称,如赖氨酸铜、白锰等.有机微量蛋元素产品被研发企业称为所谓的"第三代"微量元素添加剂.有机微量元素营养是动物营养工作者目前研究的热点之一. 相似文献
60.
Guoqing Liu Yuzhen Zhao Sumei Cao Xugang Luo Runlian Wang Liyang Zhang Lin Lu Xiudong Liao 《Journal of animal physiology and animal nutrition》2020,104(4):1052-1066
The present study was conducted to assess the relative bioavailability of selenium (Se) as Se yeast (SY) relative to sodium selenite (SS) for broilers fed a conventional corn–soybean meal diet. A total of 360 one-d-old Arbor Acres commercial broilers were randomly assigned to 5 treatments with 6 replicates per treatment in a completely randomized design involving a 2 (Se sources: SY and SS) × 2 (added Se levels: 0.20 and 0.40 mg Se/kg) factorial design of treatments plus 1 (a Se-unsupplemented control diet) for 42 days. The results showed that Se concentrations in plasma, liver, heart, breast muscle, pancreas and kidney of broilers on d 21 and 42, glutathione peroxidase (GSH-Px) activity in the pancreas on d 21 as well as in the breast muscle and pancreas on d 42, and GSH-Px mRNA levels in the liver, heart, breast muscle and pancreas on d 21 increased linearly (p < .03) as levels of added Se increased. Furthermore, a difference (p ≤ .05) between SY and SS was detected for Se concentrations in plasma, liver, heart, breast muscle, pancreas and kidney, GSH-Px activity in pancreas on both d 21 and 42, as well as pancreatic GSH-Px mRNA level on d 21. Based on slope ratios from the multiple linear regressions of the above indices, the Se bioavailabilities of SY relative to SS (100%) were 111%–394% (p ≤ .05) when calculated from the Se concentrations in plasma, liver, heart, breast muscle, pancreas, kidney and GSH-Px activities in pancreas on d 21 and 42, as well as GSH-Px mRNA level in pancreas on d 21. The results from this study indicated that the Se from SY was more available for enhancing the Se concentrations in plasma or tissues and the expression and activity of GSH-Px in pancreas of broilers than the Se from SS. 相似文献