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1.
效应代数作为一种代数结构在量子结构和量子测量的基础研究中起到重要作用,也广泛被大家关注.引入了效应代数的对偶效应代数这一新概念,讨论了对偶效应代数的一些性质.给出了一些典型效应代数的对偶效应代数的具体形式,并建立了效应代数与其对偶的密切关系.  相似文献   

2.
在效应代数中引入了 R-覆盖、N-覆盖以及 N-值伪补的概念并研究了它们的性质,讨论了效应代数中的伪补和正交补的关系,证明了若 E是具有 N-值伪补关系的格值效应代数,则 E具有 N-覆盖性质,并且橙 a ,b∈ E ,γ(a∧b)=γa∧γb 。  相似文献   

3.
为刻画实数域R上的二维交换结合代数的结构,给出了实数域R上含幺元的二维交换结合代数的分类,证明了在同构意义下实数域R上只有3类含幺元交换结合代数,即在该结合代数上存在一组基底{e,u},e是幺元,满足u2=u或u2=0或是复数域.  相似文献   

4.
研究了效应代数上态射、单调态射和弱单调态射的一些性质,证明了如果E1,E2为格效应代数,φ:E1→E2是1-1态射且φ是格同态,那么φ是单调态射.反之,若φ:E1 →E2是满的单调态射,则φ是格同态.如果E1,E2是格序列效应代数,φ:E1→E2是双射且为态射,那么φ是单调态射当且仅当φ(a∧b)=φ(a)∧φ(b),...  相似文献   

5.
2021年国际益生菌和益生元科学协会发表共识,将后生元定义为对宿主健康具有促进作用的无生命微生物和/或其成分的制剂。自此,关于后生元的研究进入热潮。相较于益生菌,后生元的益生特性不依赖于菌株活性,使其相较于活体微生物具有更高的稳定性和安全性,因此便于大规模生产及容易被消费者接受。作者概述了后生元制备技术,主要包括热加工技术(巴氏杀菌、高温灭菌、欧姆加热)及非热加工技术(脉冲电场、超声波、电离辐射),并重点综述了后生元在维持肠道健康、预防肥胖、维护皮肤健康、治疗便秘、抗糖尿病、改善口腔健康等方面的益生作用,以期为未来后生元的工业生产及明确后生元益生效应机制提供参考。  相似文献   

6.
采用等离子体发射光谱仪法(ICP)测定40~140d日龄泰和乌骨鸡体内的8种微量元素和5种常量元素的含量。结果表明,泰和乌骨鸡体内的8种微量元素含量随日龄增长先升高后降低,在70~100d达最高,常量元素在此时间段也达最高值。因此,可将泰和乌骨鸡的最佳入药时间确定为70~100d。  相似文献   

7.
正则环R的元素在“减法”偏序下作成一个偏序集,m∈R是极大元的充要条件为m^k是极大元,直有限的极大正则环是单位正则环的充要条件为mR=m^kR(m是任意极大元)。  相似文献   

8.
目的 探究六堡茶以及六堡茶原料毛茶中无机元素的含量特征。方法 以26个六堡茶成品茶和6个原料茶为研究对象, 采用电感耦合等离子质谱法测定稀土元素, 采用电感耦合等离子发射光谱法测定矿质元素。结果 六堡茶成品茶中稀土元素总量范围[(0.72~2.79) mg/kg],原料茶中稀土元素总量范围[(0.42~0.71) mg/kg],其中含量较高的稀土元素为铈(Ce)、镧(La)、钪(Sc)、钕(Nd)、钇(Y),这5种元素含量之和分别占16种稀土元素总量的82.3%(六堡茶成品茶)和89.6%(原料茶);六堡茶成品茶的矿质元素总量范围[(22655.48~37517.18) mg/kg],原料茶中矿质元素总量范围[(22083.48~35647.29) mg/kg], 其中含量较高的矿质元素为钾(K)、磷(P)、钙(Ca)、镁(Mg),这4种元素含量之和分别占19种矿质元素总量的95.6%(成品茶)和95.9%(原料茶)。结论 研究表明六堡茶成品茶中稀土元素含量显著高于原料茶(P<0.05),而矿质元素含量在二者间差异不显著(P>0.05)。  相似文献   

9.
Due to limited data-describing abilities of mushrooms to accumulate platinum group elements (PGEs) and rare-earth elements (REEs), the aim of this study was to determine, by inductively coupled plasma optical emission spectrometry followed by microwave-assisted sample digestion by nitric acid, the content of these elements in 20 mushroom species (10 above ground and 10 growing on wood), mostly edible, collected near a busy trunk road. The highest content of PGEs in above-ground mushroom species was observed in Lepista gilva and Suillus bovinus fruit bodies (0.38 ± 0.05 and 0.37 ± 0.03 mg kg?1 DW, respectively), while in mushrooms growing on wood, the highest content was observed in Pleurotus ostreatus (0.35 ± 0.04 mg kg?1 DW). The mean content of PGEs for both these groups was 0.23 ± 0.08 and 0.26 ± 0.07 mg kg?1 DW, respectively. The highest content of REEs in Suillus luteus and Tricholoma equestra was 5.03 ± 0.50 and 2.18 ± 0.56 mg kg?1 DW, respectively, but within mushrooms growing on wood in Ganoderma applanatum fruiting bodies it was 4.19 ± 0.78 mg kg?1 DW. Mean contents of REEs were 1.39 ± 1.21 and 1.61 ± 0.97 mg kg?1 DW in above-ground species and species growing on wood, respectively. Generally, the group of mushroom species growing on wood was capable of slightly higher accumulation of both REEs and PGEs. No limits have been established for both the groups until now.  相似文献   

10.
以Rh、In、Re为内标元素,建立了电感耦合等离子体质谱(ICP—MS)同时测定Cr、Pb、Cd、As、Sb 5种重金属元素及Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu15种稀土元素含量的方法。各种元素的标准曲线的线性相关系数均在0.999以上,检出限为0.001 2~0.10ng/mL。用国家标准物质GBW10052绿茶对方法进行了验证,测定值均未超出该参考物的标准值范围。利用建立的方法测定了湖南产5种黑茶的5种重金属元素及15种稀土元素含量,并对样品进行了加标回收率试验,回收率在92%~105%。为茶叶中重金属元素及稀土元素含量的测定提供了可靠的分析方法。  相似文献   

11.
考虑Meta分析中偏倚对总体效应估计的影响.在模型中引入表示偏倚的参数,构造基于偏正态分布的模型,将偏倚与异质性同时纳入模型,并进行估计,由估计量分析偏倚对异质性和总体效应的影响.在基于偏正态分布的模型下,对总体效应量采用加权最小二乘估计,并进一步修正为无偏估计.与以往基于正态分布的模型相比,该模型将偏倚进行了量化,并从总体效应的估计中予以剔除,从而使合并效应量剔除了偏倚的影响,而且较基于正态分布的模型更符合实际情况.  相似文献   

12.
Concentration levels of As, Cd, Hg, Pb, Tl, Sn, Sb Co, Cu, Mn, Se, Zn, Cr, Ni and Mo in different types of rice cultivated in irrigated fields in Brazil were evaluated. Arsenic, Cd, Pb, Zn, Mn and Cu were found in higher concentrations in brown rice samples, suggesting the prevalence of these elements in the bran. Meanwhile, lower concentrations of Pb, Mo, Cr, Se and Co were found in parboiled rice. Organic rice did not differ of cultivated conventionally rice. Thallium, Hg and Sb were not detected in any rice sample whose limits of detection were 0.7 μg kg?1, 2.5 μg kg?1 and 8 μg kg?1, respectively. The concentrations of the investigated elements were compared with those reported for polished rice and brown rice from other countries, unveiling concentrations in general at the same level for rice produced at non-contaminated sites.  相似文献   

13.
In this study, 88 randomly selected samples of butter produced in the Black Sea region of Turkey were purchased from different retail markets during different periods and investigated for toxic and essential elements content. Quantitative analyses of elements in the samples were performed using an inductively coupled plasma-mass spectroscopy (ICP-MS). Mean concentrations of As, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn in the butter samples were 18.93, 100.32, 384.66, 4199.1, 887.47, 168.64, 56.13, 16.34 and 384.66 µg kg?1, respectively. Cd and Co were detected in 19 (mean content 0.29 µg kg?1) and 81 (mean content 3.81 µg kg?1) samples of 88 butter samples, respectively. However, the dietary intake of these elements by the population of the Black Sea region is currently well below the dietary reference intake (DRI) and provisional tolerable weekly intake (PTWI) levels of essential and toxic elements.  相似文献   

14.
Twelve mineral and trace elements (Al, B, Ba, Fe, Zn, Mn, Mg, K, Na, P, Cu, Sr, and Ca) were determined in the herbs and their infusions consumed for medical purposes in Poland such as chamomile (Matricaria chamomilla L.), peppermint (Mentha xpiperita), melissa (Melissa officinalis), sage (Salvia officinalis), nettle (Urtica dioica), linden (Tilia vulgaris) and St. John's wort (Hypericum calycinum). Dry digestion procedure for total concentration and wet digestion procedure for infusions were applied under optimized conditions for dissolution of medicinal herbs. Element concentrations in herbs and their infusions were determined by ICP-OES. The accuracy and precision were verified against NCS DC 73349 - bush branches and leaves certified reference material. The result of total concentrations of elements in herb leaves shows that all herbs contain most of the elements, except K and P, in the μg/g range, and that elemental concentrations varied widely. Moreover, on the basis of experimental results for the extraction efficiencies, the elements in herb infusions were classified into three specific groups: highly-extractable (>55%) including K; moderately-extractable (20-55%) including Mg, Na, P, B, Zn and Cu and poorly-extractable (<20%) including Al, Fe, Mn, Ba, Ca and Sr. The results of analysis were evaluated statistically using ANOVA one-way and three-way analysis of variance, variance correlation test and Spearman's test.  相似文献   

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