Instantaneous measurement of the internal temperature in lithium-ion rechargeable cells

We demonstrate, in three different rechargeable lithium-ion cells, the existence of an intrinsic relationship between a cell's internal temperature and a readily measurable electrical parameter, namely the phase shift between an applied sinusoidal current and the resulting voltage. The temperature range examined spanned from −20 to 66 °C. The optimum single frequency for the phase measurement is in the 40–100 Hz range, allowing for a measurement time of much less than a second; the phase shift in this range depends predominantly on temperature, and is almost completely independent of the state-of-charge. Literature reports suggest that the observed dependence of the phase shift on temperature arises from the ionic conduction of the so-called solid-electrolyte-interphase layer between the graphite anode and the electrolyte. A meter measuring the phase shift across this interphase is analogous to a thermometer reporting the temperature, thereby providing feedback for rapid corrections of any operating conditions that might lead to the catastrophic destruction of the cell. This level of monitoring and control is distinctly different from the present safety-enabling mechanisms: typically positive thermal coefficient ceramics/plastics, or “shutdown” separators based on polyethylene that act to often permanently shut down current flow through the cell.     

Smoking reduction fails to improve clinical and biological markers of cardiac disease: a randomized controlled trial.

Cigarette reduction has been proposed as a treatment goal for smokers who are not interested in stopping completely. This randomized controlled trial was designed to determine the effect of a smoking reduction intervention on smoking behavior, symptoms of heart disease, and biomarkers of tobacco exposure. It included 152 patients with heart disease who did not intend to stop smoking in the next 30 days. Participants were randomly assigned to smoking reduction (SR) or usual care (UC). SR subjects received counseling and nicotine replacement therapy to encourage > or =50% reduction in cigarettes per day (CPD). They were followed at 1, 3, 6, 12 and 18 months to assess smoking, heart disease symptoms, quality of life and nicotine, cotinine, carbon monoxide (CO), white blood cell (WBC) count, fibrinogen, hs-C-reactive protein (hs-CRP), F2-isoprostane, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides (total NNAL), and 1-hydroxypyrene (1-HOP). At 6 months SR participants reduced by 10.9 CPD, compared with 7.4 CPD in UC (difference NS). At 18 months, 9/78 SR vs. 9/74 UC participants quit smoking. There were no significant differences between treatment groups in angina, quality of life or adverse events, nicotine, cotinine, CO, WBC count, fibrinogen, hs-CRP, F2-isoprostane, total NNAL or 1-HOP levels at any time point. To determine if smoking reduction, regardless of treatment condition, was associated with improved outcomes, we compared all subjects at 6 months to baseline (mean reduction in CPD from 27.4 to 18.1, p<.01). There were no significant changes in outcome variables except CO, which decreased by 5.5 ppm (p<.01). There were also no significant improvements considering only subjects who reduced by > or =50%, or those who had no history of reduction prior to enrollment in the study. The SR intervention did not significantly reduce CPD or toxin exposure, or improve smoking cessation or clinical outcomes compared to UC. These results emphasize the importance of abstinence for smokers with heart disease to minimize health risks from tobacco.     

Ex vivo gastrointestinal biotransformation of chlorothalonil in the germ-free and conventional rat

1. The metabolism and absorption of chlorothalonil and corresponding diglutathione and dicysteine conjugates was studied using isolated everted gastrointestinal sacs of the conventional and germ-free rat. An HPLC method was used to analyse mucosal and serosal fluids. Thiol metabolites of chlorothalonil were determined by GC/MS. 2. Low absorption of the substrates was observed, with < 4% of the radioactivity being recovered from the serosal buffers and the digestive tissues. A major part of the radioactivity was recovered from the mucosal fluids and it corresponded to unchanged chlorothalonil. Traces of unchanged chlorothalonil and mono-, di- and trimethylthio metabolites were present in serosal fluids as well as unidentified polar peaks. An important transformation (> 75%) of the chlorothalonil conjugates was observed. The di- and trimethylthio metabolites of chlorothalonil were detected from both sides of the everted gut sac of rat incubated with the diglutathione and dicysteine conjugates. 3. Few differences were observed between the conventional and germ-free rat: absorption was higher in the duodenum of germ-free rat, but tissue retention was more significant in the duodenum of the conventional rat.     

Predictors of smoking reduction without formal intervention.

The Reduction of Smoking in Cardiac Patients (ROSCAP) Study is a randomized controlled trial to test the effectiveness of a smoking reduction strategy to decrease tobacco-related harm, promote cessation, and improve biochemical and clinical indicators of toxin exposure among patients with heart disease. We analyzed baseline characteristics of patients enrolled for participation to investigate predictors of spontaneous smoking reduction prior to study enrollment. Past reducers were more likely to be males (p=.009) and had higher past peak smoking level (p<.0001) than nonreducers. Gender and number of heart disease diagnoses predicted the occurrence of spontaneous reduction and its extent. Age and a history of chronic obstructive pulmonary disease also predicted the extent of reduction. Cotinine and nicotine levels per cigarette per day were significantly higher among past spontaneous reducers than nonreducers. Spontaneous reduction is common among medically ill smokers. Past history of heart disease is a strong predictor of prior reduction. There is evidence of compensation among past spontaneous reducers.     

Quantitative three-dimensional confocal microscopy of synaptic structures in living brain tissue

In order to study changes in synaptic structure that accompany learning and memory, we have developed optical methods to visualize dendritic spines and presynaptic terminals in living, electrically monitored brain slices maintained in vitro. Focal microapplication of the fluorescent lipophilic dye DiI provides Golgi-like staining of small numbers of cells and processes that can be resolved clearly using confocal microscopy; viability of stained cells is established by exclusion of the fluorescent DNA-binding dye ethidium bromide. Serial optical sections are enhanced by deconvolution and other image processing methods. The resulting high-resolution images are combined in an automated procedure to generate three-dimensional reconstructions, in which submicron synaptic structures can be viewed and measured. These unbiased methods allow volume changes in individual, living synaptic structures to be assessed quantitatively over periods of hours or days in development or in response to stimulation, drug application, or other perturbations.     

Environmental issues for MIMO capacity

Wireless communication using multiple-input multiple-output (MIMO) systems enables increased spectral efficiency for a given total transmit power. Increased capacity is achieved by introducing additional spatial channels that are exploited using space-time coding. In this paper, the environmental factors that affect MIMO capacity are surveyed. These factors include channel complexity, external interference, and channel estimation error. The maximum spectral efficiency of MIMO systems in which both transmitter and receiver know the channel (using channel estimate feedback) is compared with MIMO systems in which only the receiver knows the channel. Channel complexity is studied using both simple stochastic physical scattering and asymptotic large random matrix models. Both uncooperative (worst-case) and cooperative (amenable to multiuser detection) interference are considered. An analysis for capacity loss associated with channel estimation error at the transmitter is introduced.     

《异域风尚》

出版社:上海人民美术出版社作为一本设计专著,本书汇集了全球的设计理念,完美表现了融合世界不同民族的各种家具、织物、配饰和艺术品等设计元素的绝妙设计风尚。通过本书,你可以发现融会了世界最漂亮设计的居室风采,也可以学到如何使你的空间更具异域风情。无论是想以一两件异国珍品来充实你的居室或重新设计的房间,本书将为你提供来自全球的各种装饰风格。     

Hierarchical microstructures in CZT

Advanced characterization tools, such as electron backscatter diffraction and transmitted IR microscopy, are being applied to study critical microstructural features and orientation relations in as-grown CZT crystals to aid in understanding the relation between structure and properties in radiation detectors. Even carefully prepared single crystals of CZT contain regions of slight misorientation, Te-particles, and dislocation networks that must be understood for more accurate models of detector response. This paper describes initial research at PNNL into the hierarchy of microstructures observed in CZT grown via the vertical gradient freeze or vertical Bridgman method at PNNL and WSU.