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301.
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303.
Synthesis, Properties, and Functionalization of Poly(ferrocenylsilane)s with Chloroalkyl Side Chains
K. Nicole Power-Billard Timothy J. Peckham Angelika Butt Frieder Jäkle Ian Manners 《Journal of Inorganic and Organometallic Polymers》2000,10(4):159-168
A series of poly(ferrocenylsilane)s containing chloroalkyl side chains of increasing length is reported. By reacting fcLi2·
tmeda with Cl2SiMeR, the corresponding [1]ferrocenophanes were prepared (2a, R=CH2Cl; 2b, R=CH2CH2Cl; and 2c, R=CH2CH2CH2Cl). Transition metal-catalyzed or thermal ring-opening polymerization (ROP) of these monomers yielded the polyferrocenes 3a, 3b, and 3c. The chlorine substituents of polymers 3a and 3b were unreactive toward nucleophilic substitution. In contast, polymer 3c could be reacted with 4-dimethylaminopyridine in DMF to afford the water-soluble poly(ferrocenylsilane) 4. This represents a new method for the preparation of water-soluble polyferrocenes. 相似文献
304.
Governments and corporations are increasingly adopting circular economy strategies to meet the need of decoupling growth from resource consumption. However, the world economy is far from being circular, with some of the reasons including lack of transparency, standardization, and data sharing. Digitalization can help overcome these challenges, thus making it a key enabler of the circular economy. This review looks at the concept of a digital product passport as a tool for implementing and scaling the circular economy. It discusses opportunities and challenges related to further development and adoption of digital product passports. Finally, it examines the battery passport, drafted in the EU Battery regulation, as one of the first examples of a digital product passport required by law. 相似文献
305.
木窗,包括纯木窗,铝包木窗和木铝复合窗,作为一种相对新兴的窗型,近些年在国内发展迅速.而作为一种成熟产品,木窗在欧洲已经存在完整的生产和安装标准.我们可以借鉴国外的成熟技术加速自身完善. 相似文献
306.
The sn position of fatty acids in seed oil lipids affects physiological function in pharmaceutical and dietary applications. In
this study the composition of acyl-chain substituents in the sn positions of glycerol backbones in triacylglycerols (TAG) have been compared. TAG from native and transgenic medium-chain
fatty acid-enriched rape seed oil were analyzed by reversed-phase high performance liquid chromatography coupled with online
atmospheric-pressure chemical ionization ion-trap mass spectrometry. The transformation of summer rape with thioesterase and
3-ketoacyl-[ACP]-synthase genes of Cuphea lanceolata led to increased expression of 1.5% (w/w) caprylic acid (8:0), 6.7% (w/w) capric acid (10:0), 0.9% (w/w) lauric acid (12:0), and 0.2% (w/w) myristic acid (14:0). In contrast, linoleic (18:2n6) and alpha-linolenic acid (18:3n3) levels decreased compared with the
original seed oil. The TAG sn position distribution of fatty acids was also modified. The original oil included eleven unique TAG species whereas the transgenic
oil contained sixty. Twenty species were common to both oils. The transgenic oil included trioctadecenoyl-glycerol (18:1/18:1/18:1)
and trioctadecatrienoyl-glycerol (18:3/18:3/18:3) whereas the native oil included only the latter. The transgenic TAG were
dominated by combinations of caprylic, capric, lauric, myrisitic, palmitic (16:0), stearic (18:0), oleic (18:1n9), linoleic,
arachidic (20:0), behenic (22:0), and lignoceric acids (24:0), which accounted for 52% of the total fat. In the original TAG
palmitic, stearic, oleic, and linoleic acids accounted for 50% of the total fat. Medium-chain triacylglycerols with capric
and lauric acids combined with stearic, oleic, linoleic, alpha-linolenic, arachidic, and gondoic acids (20:1n9) accounted
for 25% of the transgenic oil. The medium-chain fatty acids were mainly integrated into the sn-1/3 position combined with the essential linoleic and alpha-linolenic acids at the sn-2 position. Eight species contained caprylic, capric, and lauric acids in the sn-2 position. The appearance of new TAG in the transgenic oil illustrates the extensive effect of genetic modification on fat
metabolism by transformed plants and offers interesting possibilities for improved enteral applications. 相似文献
307.
Total and individual glucosinolate contents of broccoli cv Marathon were assessed at ambient CO2 (430–480 ppm) and elevated atmospheric CO2 (685–820 ppm) to determine the ecological relationship between changing atmospheric CO2 concentrations and phytochemicals. Elevated atmospheric CO2 concentration had a differing effect on individual glucosinolates and glucosinolate groups. Total glucosinolate content increased
at elevated atmospheric CO2 concentration as a result of a strong increase in both methylsulfinylalkyl glucosinolates glucoraphanin and glucoiberin.
In contrast, indole glucosinolates simultaneously decreased, predominantly because of a reduction of glucobrassicin and 4-methoxy-glucobrassicin
contents. We conclude that changes in N content and N/S ratios as well as alterations in photochemical processes at elevated
atmospheric CO2 concentration can influence total and individual glucosinolates contents of Brassicaceae, as demonstrated in the greenhouse, for broccoli. 相似文献
308.
309.
Lundgren A Hedlund J Andersson O Brändén M Kunze A Elwing H Höök F 《Analytical chemistry》2011,83(20):7800-7806
A single-chip electrochemical method based on impedance measurements in resonance mode has been employed to study lipid monolayer and bilayer formation on hydrophobic alkanethiolate and SiO(2) substrates, respectively. The processes were monitored by temporally resolving changes in interfacial capacitance and resistance, revealing information about the rate of formation, coverage, and defect density (quality) of the layers at saturation. The resonance-based impedance measurements were shown to reveal significant differences in the layer formation process of bilayers made from (i) positively charged lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-ethylphosphocholine (POEPC), (ii) neutral lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) on SiO(2), and (iii) monolayers made from POEPC on hydrophobic alkanethiolate substrates. The observed responses were represented with an equivalent circuit, suggesting that the differences primarily originate from the presence of a conductive aqueous layer between the lipid bilayers and the SiO(2). In addition, by adding the ion channel gramicidin D to bilayers supported on SiO(2), channel-mediated charge transport could be measured with high sensitivity (resolution around 1 pA). 相似文献
310.
Excretion of Avenanthramides,Phenolic Acids and their Major Metabolites Following Intake of Oat Bran 下载免费PDF全文
Manuel Y. Schär Giulia Corona Gulten Soycan Clemence Dine Angelika Kristek Sarah N. S. Alsharif Volker Behrends Alison Lovegrove Peter R. Shewry Jeremy P. E. Spencer 《Molecular nutrition & food research》2018,62(2)