Solution properties of single-walled carbon nanotubes   总被引：3，自引：0，他引：3  

J Chen  MA Hamon  H Hu  Y Chen  AM Rao  PC Eklund  RC Haddon 《Science (New York, N.Y.)》1998,282(5386):95-98

Naked metallic and semiconducting single-walled carbon nanotubes (SWNTs) were dissolved in organic solutions by derivatization with thionychloride and octadecylamine. Both ionic (charge transfer) and covalent solution-phase chemistry with concomitant modulation of the SWNT band structure were demonstrated. Solution-phase near-infrared spectroscopy was used to study the effects of chemical modifications on the band gaps of the SWNTs. Reaction of soluble SWNTs with dichlorocarbene led to functionalization of the nanotube walls.  相似文献   

Design of a surface alloy catalyst for steam reforming   总被引：1，自引：0，他引：1  

F Besenbacher  I Chorkendorff  BS Clausen  B Hammer  AM Molenbroek  JK Norskov  I Stensgaard 《Science (New York, N.Y.)》1998,279(5358):1913-1915

Detailed studies of elementary chemical processes on well-characterized single crystal surfaces have contributed substantially to the understanding of heterogeneous catalysis. Insight into the structure of surface alloys combined with an understanding of the relation between the surface composition and reactivity is shown to lead directly to new ideas for catalyst design. The feasibility of such an approach is illustrated by the synthesis, characterization, and tests of a high-surface area gold-nickel catalyst for steam reforming.  相似文献   

水稻物质生产对稻田甲烷排放的影响   总被引：1，自引：0，他引：1  

黄耀  Ronald L.Sass  Frank M.Fisher 《农业环境科学学报》1999,18(4):2

以研 究水稻 物质生产 对稻田 甲烷排 放影响为 目的的 大田与 盆栽 试验于１９９４ —１９９５ 年在美国德克萨斯州进行。对同期观测的稻田甲烷排放量与水稻干物质积累资料的分析表明, 在类似的气候、土壤及水稻栽培管理条件下, 稻田甲烷排放的季节总量随水稻生产力水平的提高而增加; 甲烷日排放通量与水稻干物质积累呈正相关;水稻生长中、后期的物质生产对甲烷排放的贡献大于前期。  相似文献   

Defining a Safe Operating Space for inland recreational fisheries          下载免费PDF全文

Stephen R Carpenter  William A Brock  Gretchen J A Hansen  Jonathan F Hansen  Joseph M Hennessy  Daniel A Isermann  Eric J Pedersen  K Martin Perales  Andrew L Rypel  Greg G Sass  Tyler D Tunney  M Jake Vander Zanden 《Fish and Fisheries》2017,18(6):1150-1160

The Safe Operating Space (SOS) of a recreational fishery is the multidimensional region defined by levels of harvest, angler effort, habitat, predation and other factors in which the fishery is sustainable into the future. SOS boundaries exhibit trade‐offs such that decreases in harvest can compensate to some degree for losses of habitat, increases in predation and increasing value of fishing time to anglers. Conversely, high levels of harvest can be sustained if habitat is intact, predation is low, and value of fishing effort is moderate. The SOS approach recognizes limits in several dimensions: at overly high levels of harvest, habitat loss, predation, or value of fishing effort, the stock falls to a low equilibrium biomass. Recreational fisheries managers can influence harvest and perhaps predation, but they must cope with trends that are beyond their control such as changes in climate, loss of aquatic habitat or social factors that affect the value of fishing effort for anglers. The SOS illustrates opportunities to manage harvest or predation to maintain quality fisheries in the presence of trends in climate, social preferences or other factors that are not manageable.  相似文献   

Synthesis of new tetronamides displaying inhibitory activity against bloom‐forming cyanobacteria     

Jaime AM Acosta  Milandip Karak  Luiz CA Barbosa  John Boukouvalas  Andrea Straforini  Giuseppe Forlani 《Pest management science》2020,76(2):779-788

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A case of Eisenmenger complex in a calf     

B Sass  T F Albert 《The Cornell veterinarian》1970,60(1):61-65

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A new tool to monitor training and performance of sport horses using global positioning system (GPS) with integrated GSM capabilities   总被引：1，自引：0，他引：1  

Hebenbrock M  Düe M  Holzhausen H  Sass A  Stadler P  Ellendorff F 《DTW. Deutsche tier?rztliche Wochenschrift》2005,112(7):262-265

Global Positioning Systems (GPS) are considered suitable to monitor the position and velocity of horses during cross-country competition or in training. Furthermore, simultaneous recording of life data such as heart rate could be useful to assess the horse's condition during exercise. To test the suitability and reliability of a commercially available GPS system with integrated heart rate recording system and with built in GSM for data transmission, the Fidelak Equipilot Type EP-2003-15/G-2.11 (EP-15/G) was evaluated first for reliability of pulse recording from a pulse generator within the physiological range of horses; furthermore distance, velocity and heart rate recordings were carried out on a standard 1000 m field track with five repetitions. Agreement (% deviation from actually measured distance and from stopwatch-distance based velocity calculations) and variability (Coefficient of Variation for distance, velocity, heart rate) were calculated. From the results it was safe to assume that the heart rate sensor recorded horse heart rates at a high degree of accuracy. Overall distances and velocities are in high agreement with actually measured values. However, overall variability expressed in terms of relative variability (C.V.) is smaller for distance recording (C.V. 0.68%) when compared to velocity (C.V. 1.01%). The system tested is suitable and reliable for simultaneously recording of distance, velocity and heart rates for horses during cross country exercise. GPS-based monitoring of movement along with simultaneous recording of physiological data and the possibility to call upon data will not only be of benefit for training horses or for surveillance during competition, it may also be suitable for distant patient monitoring and in behavioural studies as well as in veterinary medicine in general.  相似文献   

Effectiveness of controlled internal drug release device treatment to alleviate reproductive seasonality in anestrus lactating or dry Barki and Rahmani ewes during non‐breeding season          下载免费PDF全文

MY EL‐Mokadem  ANM Nour El‐Din  TA Ramadan  AM Rashad  TA Taha  MA Samak  MH Salem 《Reproduction in domestic animals》2018,53(2):319-325

This study aimed to evaluate the effectiveness of hormonal treatments on ovarian activity and reproductive performance in Barki and Rahmani ewes during non‐breeding season. Forty‐eight multiparous ewes, 24 Barki and 24 Rahmani ewes were divided into two groups, 12 lactating and 12 dry ewes for each breed. Controlled internal drug release (CIDR) device was inserted in all ewes for 14 days in conjunction with intramuscular 500 IU equine chronic gonadotrophin (eCG) at day of CIDR removal. Data were analysed using PROC MIXED of SAS for repeated measures. Breed, physiological status and days were used as fixed effects and individual ewes as random effects. Barki ewes recorded higher (p < .05) total number of follicles, number of large follicles, serum estradiol concentration and estradiol: progesterone (E₂:P₄) ratio compared to Rahmani ewes. Lactating ewes recorded higher (p < .05) number of small follicles and lower concentration of total antioxidant capacity (TAC) compared to dry ewes. Number and diameter of large follicles recorded the highest (p < .05) values accompanied with disappearance of corpora lutea at day of mating. Serum progesterone concentration recorded lower (p < .05) value at day of mating and the highest (p < .05) value at day 35 after mating. CIDR‐eCG protocol induced 100% oestrous behaviour in both breeds, but Rahmani ewes recorded longer (p < .05) oestrous duration compared to Barki. Conception failure was higher (p < .05) in Barki compared to Rahmani ewes. In conclusion, CIDR‐eCG protocol was more potent in improving ovarian activity in Barki compared to Rahmani ewes, but this protocol seems to induce hormonal imbalance in Barki ewes that resulted in increasing conception failure compared to Rahmani ewes.  相似文献   

Can the Genetic Origin Affect Rabbit Seminal Plasma Protein Profile along the Year?          下载免费PDF全文

L Casares‐Crespo  AM Talaván  MP Viudes‐de‐Castro 《Reproduction in domestic animals》2016,51(2):294-300

The study was designed to evaluate the influence of genetic origin on rabbit seminal plasma protein profile variation along the year. Seminal plasma of rabbits from line A (maternal line) and R (paternal line) collected during a natural year was subjected to polyacrylamide gel electrophoresis (SDS‐PAGE). The electrophoretic profile of rabbit seminal plasma resulted in multiple protein bands of different intensity ranging from 9 to 240 kDa. Results showed that seven protein bands were significantly different between genetic lines, and among these, three protein bands were significantly different between seasons. The differentially expressed proteins were identified by MALDI‐TOF/TOF or LC‐MS/MS analysis and were the following ones: FAM115E‐like (220, 113 and 59 kDa), ectonucleoside triphosphate diphosphohydrolase 3 isoform X2 (72 kDa), annexin A5 (32 kDa), lipocalin allergen Ory c 4 precursor (19 kDa), and haemoglobin subunit zetalike (13 kDa) between genetic lines and FAM115E‐like (113 kDa), haemoglobin subunit zetalike (13 kDa) and β‐nerve growth factor (12 kDa) between seasons. These results indicate that proteins from rabbit seminal plasma are under both seasonal control and genetic control. Furthermore, the differential presence of these proteins could be one of the causes explaining the differences observed in fertility and seminal parameters between these two lines in earlier studies.  相似文献   

ABERRANT HETEROTHALLISM IN A HOMOTHALLIC COPRINUS     

Sass JE 《Science (New York, N.Y.)》1928,68(1770):548

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