Techniques for realizing practical application of sulfur cathodes in future Li-ion batteries

The development of lithium-sulfur batteries is associated with many problems. These problems include polysulfide dissolution, the shuttle phenomenon, the low electric and ionic conductivity of S, and the volume change that occurs during charge and discharge. In this review, various elemental techniques for overcoming these problems are summarized from the standpoints of the supporting materials. These techniques include preventing polysulfide dissolution from the cathodes through physical and chemical adsorption on the supporting materials, the use of electrolytes that do not dissolve polysulfides via the coordination of Li⁺ and solvents, and the use of ion-exchange polymers to permeate Li⁺ selectively. The following approaches to enable practical applications of S cathodes in future Li-ion batteries are introduced: the utilization of Li-free anode materials, such as C and Si; the use of Li₂S cathodes, which are prepared via a pre-lithiation process; and increasing the areal capacity of the S cathode by using a suitable current collector such as Al foam, thus providing a large amount of space for Li⁺ to migrate and the electron-conductive path. The utilization of an Al foam current collector is one of the promising approaches to creating a cost-effective Li-ion battery owing to the established mass production of Al foam for use in NiMH batteries; such Li-ion battery can achieve an unprecedentedly high areal capacity of 21.9 mAh cm^?2. Owing to the resulting areal capacity, the possibility of developing a lithium-sulfur battery with an energy density greater than 200 Wh kg^?1 has been demonstrated. Consequently, the combination of these approaches, as introduced in this review, would help create a bright, sustainable society.     

Synthesis of lipophilic bisanthracene fluorophores: versatile building blocks toward the synthesis of new light-harvesting dendrimers

Lipophilic bisanthracene-based fluorophore and its derivatives were synthesized by the Suzuki-Miyaura cross-coupling reaction of 9-anthrylboronic acid with a substituted dibromobenzene. In addition to desirable fluorescent properties, these molecular systems were demonstrated to serve as versatile building blocks toward the synthesis of two types of new light-harvesting dendrimers due to their chemical stability.     

Surgical effects on soft tissue produced by a 405-nm violet diode laser in vivo

This study evaluated the surgical performance of a 405-nm diode laser in vivo, using living rat liver tissue. Tissue was incised by irradiation with the laser at low output power ranging from 1 W (722 W/cm²) to 3 W (2165 W/cm²) on a manual control at a rate of 1 mm/s. As a control, incisions using a stainless scalpel were compared. Immediately after operation, the surface of the incisions was macroscopically observed and histopathologically evaluated by microscopy. Laser-ablated liver tissue was smooth with observable signs of remnant carbonization and easily acquired hemostasis. The thickness of the denatured layer increased in proportion to the output power; the coagulation layer did not thicken accordingly. Bleeding could not be stopped for tissues incised with the stainless scalpel. The 405-nm diode laser thus proved to be effective for ablating soft tissue with high hemostatic ability at low power.     

Convenient green preparation of dipeptides using unprotected α-amino acids

Dipeptides and amides were obtained in high yields from N-carbobenzyloxy α-amino acids and 3-phenylpropanoic acid with unprotected α-amino acids via the corresponding mixed carbonic carboxylic anhydrides using ethyl chloroformate and triethylamine by an ecological and convenient method in which the protection of C-terminals is not needed.     

A practical synthesis of L-ribose

L-Ribose was synthesized by a simple four-step method with overall yield of 76.3% from a protected L-arabinose derivative, which is a compatible intermediate for the synthesis of L-deoxyribose. The key step of this strategy is the Swern oxidation and subsequent stereoselective reduction accompanied by inversion of the 2-hydroxy group of protected L-arabinose.     

Palladium-catalyzed multiple arylation of thiophenes

Secondary 2-thiophenecarboxamides efficiently undergo unique triarylation accompanied by formal decarbamoylation under palladium catalysis. 3-Substituted thiophenes, especially having an electron-withdrawing group, can also be triarylated.     

Crying and Behavioral Characteristics in Premature Infants

The aims of this study were to analyze 1) whether there was the relationship between the neonatal behavioral characteristics and amount of crying in premature infants at term age, and 2) what kind of difference between infants with high levels of crying and cry less on neonatal behavioral characteristics using the Neonatal Behavioral Assessment Scale (NBAS). The study participants consisted of 69 healthy low birth-weight infants who were admitted to the NICU at the Nagasaki University Hospital, Nagasaki, Japan. This study analyzed the relationship between NBAS scores measured neonatal behavioral performance and crying at term age. This study results indicate that there was significant statistical negative correlation between the amount of total daily crying and Habituation, Range of state, Regulation of state, and Autonomic stability cluster scores and some individual items scores (Response decrement to light, Response decrement to tactile of foot, Alert responsiveness, Examiner persistence, Motor maturity, Irritability, General irritability, Cuddliness, Consolability, Self-quieting activity, and State regulation). The high levels crying group also showed higher responsivity than less crying group in the items of Peak of excitement, Rapidity of build-up, Irritability and General irritability. In conclusion, neonatal behavioral characteristics such as poor inhibit discrete stimuli while asleep, hyper-responsivity and poor state regulation abilities were risk factors of high levels of crying.     

Analysis of an SPP/G/1 system with multiple vacations and E-limited service discipline

Many researchers have studied variants of queueing systems with vacations. Most of them have dealt with M/G/1 systems and have explicitly analyzed some of their performance measures, such as queue length, waiting time, and so on. Recently, studies on queueing systems whose arrival processes are not Poissonian have appeared. We consider a single server queueing system with multiple vacations and E-limited service discipline, where messages arrive to the system according to a switched Poisson process. First, we consider the joint probability density functions of the queue length and the elapsed service time or the elapsed vacation time. We derive the equations for these pdf's, which include a finite number of unknown values. Using Rouché's theorem, we determine the values from boundary conditions. Finally, we derive the transform of the stationary queue length distribution explicitly.     

Ein zus?tzlicher Test zur modernen Theorie der Molekulargewichts-Fraktionierung auf Grund der L?slichkeits-Differenz

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