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21.
Oxide-confined top-emitting 850 nm and bottom-emitting 980 nm vertical-cavity surface-emitting laser (VCSEL) 8/spl times/8 arrays were designed and fabricated for applications of optical interconnects. The arrays were flip-chip bonded onto sapphire substrates that contain complimentary metal-oxide-semiconductor (CMOS) driver and fan-out circuitries. The off-sited bonding contacts and minimized bonding force produced very high yield of the hybridization process without causing damage to the VCSEL mesas. The hybridized devices were further mounted either on printed circuit board (PCB) or in 68-pin pin-grid-array (PGA) packages. The transparent sapphire substrate allowed optical outputs from the top-emitting VCSEL arrays to transmit directly through without additional substrate removal procedure. Lasing thresholds below 250 /spl mu/A for 850 nm VCSELs and 800 /spl mu/A for 980 nm VCSEL were found at room temperature. The oxide confinement apertures of VCSELs were measured to be around 6 /spl mu/m in diameter. High-speed data transmission demonstrated a bandwidth of up to 1 Gbits/s per channel for these hybridized VCSEL transmitters.  相似文献   
22.
Herein, a CoCrFeMnNi high-entropy alloy with reduced Cr content and with the addition of 2 at% C interstitial is processed via high-pressure torsion (HPT) under 6.5 GPa by three turns at room and cryogenic temperatures. The microstructure is investigated by transmission electron microscopy (TEM) and atom probe tomography (APT). The results indicate that C atoms segregate at the boundaries of the nanograins in the sample processed at room temperature, while the sample processed at cryogenic temperature does not show any notable segregations of carbon.  相似文献   
23.
140 Milcherzeugnisse aus verschiedenen Regionen Deutschlands wurden 2006 auf Dioxine, dioxin?hnliche PCB und nicht dioxin?hnliche PCB untersucht. Insgesamt wurden 66 K?se-, 23 Butter- und 51 Quark- bzw. Joghurterzeugnisse analysiert. Die Probenahme erfolgte in Superm?rkten und Einzelhandelsgesch?ften auf der Basis der Produktionsmengen in den einzelnen Bundesl?ndern der Bundesrepublik Deutschland. Die Dioxinkonzentrationen und die Summe der WHO-TEQ blieben weit unter den EU-Grenzwerten von 3 pg WHO-PCDD/F-TEQ/g Fett und 6 pg WHO-PCDD/F-PCB-TEQ/g Fett. Die Dioxingehalte lagen bei niedrigen 0,07–0,53 pg WHO-PCDD/F-TEQ/g Fett mit einem arithmetischen Mittelwert von 0,19 pg WHO-PCDD/F-TEQ/kg Fett. Die WHO-PCDD/F-PCB-TEQ Gehalte lagen zwischen 0,21 und 2,1 pg WHO-TEQ/g Fett, mit einem mittleren Gehalt von 0,76 pg WHO-TEQ/g Fett. Regionale Abh?ngigkeiten und Unterschiede zwischen den einzelnen Produktgruppen konnten nicht festgestellt werden. Langj?hrige Messungen der Dioxingehalte in Butter und K?se aus Schleswig-Holstein zeigen über den Zeitraum von 13 Jahren eine deutliche Abnahme der Gehalte von 0,43 auf 0,19 pg WHO-PCDD/F-TEQ/g Fett.  相似文献   
24.
25.
It has been shown that stimulation of the uterus of mares by the daily taking of biopsies can result in the occurrence of oestrous symptoms. This is accompanied by some follicular growth and a progesterone content in the blood often higher than 1 ng/ml. The following observations suggest that this progesterone originates in the uterus and not in the ovaries: (1) no active corpora lutea appeared to be present in the ovaries after ovariectomy, (2) ovariectomized mares showed the same oestrous symptoms in similar experiments and even mating took place, (3) in the uterine biopsies the concentration of the compound referred to as "5.4", which is assumed to be easily convertible into progesterone, had already increased considerably in the second biopsy, (4) administration of stilboestrol reduced the rise of the progesterone level in the uterine biopsies as well as in the blood. The absence of oestradiol-17 beta in the ovarian follicles and the fact that ovariectomized mares also come into heat suggest that oestrogens cannot be held responsible for the oestrous symptoms in these mares. Our experiments demonstrate that the uterus can be involved in sexual behaviour and the formation of steroids.  相似文献   
26.
A range of conventionally and organically farmed Pangasius or sutchi catfish fillets available on the German market were analysed to compare both composition and quality. Differentiation of Pangasius hypophthalmus from Pangasius bocourti was achieved by RFLP-SSCP analysis. The protein content of conventionally farmed fillets ranged between 13.3 and 15.7%, whereas organically produced fillets had significantly higher protein contents of between 17.0 and 17.4%. No difference in the fat content between farming methods was observed, which varied between 1.4 and 3.2%. Polyunsaturated fatty acids represented about 24% of the total fatty acids with a high level of linoleic acid. The comparison of the proximate composition indicated that water was added to most of the conventionally farmed products, in different amounts, as well as water-binding capacity enhancing additives. Differential scanning calorimetry was used to demonstrate the presence of polyphosphate on muscle proteins. Differences in texture, water-binding capacity and colour are discussed.  相似文献   
27.
A variant form of Creutzfeld–Jacob disease in humans is associated with the consumption of food contaminated with the bovine central neural system. This has focused attention on the need for procedures to detect tissues of the neural system in meat and meat products. A method was developed for the identification of myelin glycoproteins in bovine neural tissue. The glycosylated structures of glycoproteins in different protein mixtures from central nervous system (CNS) and peripheral nervous system (PNS) isolated from bovine myelin were identified by the specific lectin–glycoprotein reactions. Digoxigenin-labeled lectins bonded to the terminal glycoconjugate sequences of nine CNS glycoproteins ranging from 15 to 200 kDa and four PNS glycoproteins ranging from 22 to 105 kDa. Datura stramonium (DSA) recognized the epitope Galβ1–4GlcNAc by two CNS and three PNS glycoproteins. Maackia amurensis (MAA) recognized the epitope NeuAcα2–3Gal by four CNS and two PNS glycoproteins. The peanut Arachis hypogaea (PNA) reacted with the high molecular CNS glycoprotein (200 kDa) with the sequence Galβ1–3GalNAc. Galanthus nivalis (GNA) bonded to mannose subunits linked α1–3 and α1–6 by six CNS glycoproteins with molecular weights between 17 and 200 kDa. Four of these glycoproteins were recognized from monoclonal antibodies against the “HNK-1 epitope”.  相似文献   
28.
    
Summary The direct capillary gas Chromatographic separation oftrans--ionone andtrans--damascone enantiomers is reported using heptakis(2,3,6-tri-O-methyl)--cyclodextrin in polysiloxane as a suitable chiral stationary phase. The method described has been applied to determine the naturally occurring enantiomeric composition oftrans--ionone in the absolutes of the flowers ofBoronia megastigma Nees andOsmanthus fragrance Lour., Costus root oil (Saussurea lappa Clarke) as well as in odor concentrates of violet flowers (Viola odorata L.), fresh raspberries, carrots and vanilla pods. Furthermore, the optical purity oftrans--ionone in the solvent extracts of distilled alcoholic raspberry beverage, raspberry fruit juice concentrate and black tea was investigated.Trans--ionone was either isolated by headspace stripping in vacuo or by organic solvent extraction and subsequently enriched by multidimensional preparative Chromatographic techniques.Trans--damascone was isolated from Virginia tobacco extract and from black tea aroma and was enriched for direct chirospecific analysis by medium pressure liquid chromatography followed by multidimensional preparative capillary gas chromatography. The importance of chirality as an essential criterion for the discrimination of natural and nature-identical aromas is discussed briefly.
Chirale Analysen von Aroma-und etherischen Öl-Inhaltsstoffen Teil B. Direkte Trennung der Enantiomeren von trans--Ionon und trans--Damascon mittels Inklusionsgaschromatographie
Zusammenfassung Mit Heptakis(2,3,6-tri-O-methyl)--cyclodextrin in Polysiloxan als chiraler stationärer GC-Phase können die Enantiomeren vontrans--Ionon undtrans--Damascon direkt stereodifferenziert werden. Mit der beschriebenen Methode wird die Enantiomerenzusammensetzung vontrans--Ionon in den Absolues vonBoronia megastigma Nées undOsmanthus fragrance Lour., in Costuswurzelöl (Saussurea lappa Clarke), in den Headspace-Konzentraten von Veilchenblüten, frischen Himbeeren, Karotten und Vanilleschoten sowie in den Lösungsmittelextrakten von Himbeergeist, Himbeerfruchtsaftkonzentrat und schwarzem Tee bestimmt.Trans--Ionon wurde aus den genannten Naturprodukten mit Hilfe von multidimensionalen präparativen chromatographischen Trenntechniken angereichert und isoliert.Trans--Damascon wurde durch die Kombination MPLC/präparative Capillargaschromatographie aus Virginia Tabakextrakt und aus dem Aromastoffspektrum von schwarzem Tee erhalten und in s eine Enantiomeren aufgetrennt. Die Bedeutung der Chiralität als Beurteilungskriterium zur Unterscheidung natürlicher und naturidentischer Aromastoffe wird kurz diskutiert.
  相似文献   
29.
过去几十年中,湿巾市场总体上快速增长.预计2018-2023年,个人护理湿巾销售额复合年均增长率为7.9%,按非织造布用量计的复合年均增长率为8.0%. 在个人护理湿巾中,湿厕纸是近年来快速发展的产品类别.湿厕纸主要采用气流成网、水刺、湿法水刺非织造布为基材,其中以湿法水刺为主流.  相似文献   
30.
Summary The extraction of fish muscle protein using SDS containing solubilization buffers was studied varying the time and the temperature of solubilization, as well as pH and SDS concentration of the buffer. At pH < 6 the myofbrillar proteins were incompletely solubilized; temperatures of 80-100 °C resulted in protein degradation observable in the SDS-PAGE.Samples of fish muscle containing high amounts of formaldehyde (50 mmoles FA/kg wet weight) could only be solubilised at 100 °C; on the other hand it was possible to solubilize cooked and/or canned products under mild conditions (2% SDS, 1% 2-ME, pH 8.9, shaking for 2 h at 60 °C).
Solubilisierung von Fischmuskelproteinen durch Natriumdodecylsulfathaltige Puffer
Zusammenfassung Der Einfluß von Solubilisierungszeit und -temperatur, des pH-Wertes und der SDS-Konzentration des Solubilisierungspuffers auf die Extraktion von Fischmuskelproteinen wurde überprüft. Bei pH-Werten < 6 wurden die myofbrillären Proteine nur unvollständig gelöst; Solubilisierungstemperaturen von 80 bis 100 °C führten zu einem in der SDS-PAGE sichtbaren Proteinabbau. Fischmuskelproben mit hohem Formaldehydgehalt (50 mmole FA/kg Feuchtgewicht) ließen sich nur bei 100 °C vollständig solubilisieren; demgegenüber gelang die weitgehende Solubilisierung gegarter und/oder sterilisierter Produkte unter milden Bedingungen (2% SDS, 1% 2-ME, pH 8,9; 2stündiges Schütteln bei 60 °C).

Abbreviations FA formaldehyde - IEF isoelectric focusing - 2-ME 2-mercaptoethanol - PA polyacrylamide - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - SDS sodium dodecyl sulfate - TMAO trimethylamine oxide - Tris Tris (hydroxymethyl)methylamine  相似文献   
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