Scavenging of “Dead Sulfur” and “Dead Lithium” Revealed by Integrated–Heterogeneous Catalysis for Advanced Lithium–Sulfur Batteries

The simultaneous engineering of sulfur cathode and Li anode is critical for electrolyte-starved high energy density Li–S batteries, in which slow electrochemical conversions and side chemical reactions of dead sulfur are found to be the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li–S batteries. Herein, this work challenges the conventional wisdom of heterogeneous and homogeneous catalyses in Li–S batteries and proposes the concept of integrated–heterogeneous catalysis to simultaneously scavenge the dead sulfur and dead lithium to compensate the active materials sulfur and lithium loss simply through adding a small amount of ZnI₂ into conventional electrolyte of Li–S cells. Regulated by integrated–heterogeneous catalysis, over 1300 h of cycling is realized in Li||Li symmetric cells, revealing superb compatibility of the ZnI₂-incorporated electrolyte with lithium metal. Meanwhile, the ZnI₂ shows good prospects in promoting the reutilization of dead sulfur in both theoretical calculation and experimental tests. Practically, a high initial capacity of 1170 mAh g⁻¹ with decent cycling stability is achieved in electrolyte-starved and high-loading pouch cells (5.0 µL mg⁻¹ and 5.2 mg cm⁻²).     

Comment on “Novel lossless and lossy grounded inductor simulators consisting of a canonical number of components”

A recently published paper (Singh, Analog Integr Circuit Signal Process, 62:327–332, 2010) dealing with the relationship between the Barkhausen condition for oscillation and the well known Nyquist stability criterion for systems with feedback is highly appreciated. However, it seems to be necessary to place some comments on it. The circuit examples presented in the cited paper as well as the conclusions will be critically reviewed. Apparently, there is still no sufficient oscillation condition. Therefore, the necessity to complete the existing oscillation criterion with a sufficient condition is emphasized.     

New IC package,assembly technique by means of a “blind” alignment “flip-chip” method and assembling facilities

俄罗斯专家Vladimir V.Novikov提出了一种封装新技术,欲寻求技术和投资合作。有意者请与Vladimir V.Novikov本人或本刊编辑部联系。     

A “Nano-Courier” for Precise Delivery of Acetylcholine and Melatonin by C5a-Targeted Aptamers Effectively Attenuates Reperfusion Injury of Ischemic Stroke

Overactive inflammatory response and excessive oxidative stress are the main pathophysiological culprits for cerebral ischemia/reperfusion injury (IRI) that arouse neuronal damage . The neurotransmitter acetylcholine (ACh) exerts anti-inflammatory roles by stimulating α7 nicotinic acetylcholine receptor (α7nAChR) on microglia to activate the cholinergic anti-inflammatory pathway. Simultaneously, as a circadian rhythm-dependent hormone , melatonin (MT) possesses promising neuroprotective effects that eliminate reactive oxygen species (ROS) in the ischemic region. Relying on these, a biocompatible fluorescein isothiocyanate (FITC)-labeled SiO₂@PAA-MT/ACh nanospheres are constructed to effectively alleviate oxidative stress and polarize microglial phenotype to suppress inflammatory response in cerebral IRI. Despite of biosafety and curative effects of ACh and MT, the poor aggregation in ischemic penumbra hinders their neuroprotection. To address that, complement component 5a (C5a) is used as a molecular target for delivery of ACh and MT. C5a conspicuously exists at local inflammatory sites of cerebral IRI, recruits immune cells, and mediates further release of inflammatory cytokines. Upon binding of anti-C5a (aC5a) aptamers onto FITC-labeled SiO₂@PAA-MT/ACh nanospheres, they can effectively target the ischemic penumbra and promote neurological recovery. Taken together, the current study suggests that the FITC-labeled SiO₂@PAA-MT/ACh-aC5a nanospheres after intravenous (i.v.) administration can act as an effective targeted nanotherapy to salvage neurons in cerebral IRI.     

A model of a metallic quantum nanotransistor with a Coulomb-blockage gate in “magic” Au55 and Ag55 nanocrystals with speed of 1011 Hz

A model of a parallel metallic quantum nanotransistor with a Coulomb-blockage gate in “magic” nanocrystals Au₅₅ and Ag₅₅ with the speed of 10¹¹ Hz having sizes of 100 × 100 × 12 nm³ is suggested and calculated. It is shown that the gate-opening threshold for this model with the source-drain potential of 2.74 V is 0.2 V, and the total current of 2500 elementary single-electron nanotransistors connected in parallel is 2 × 10^?5 A, which is comparable with a current in terahertz semiconductor nanotransistors. It is shown that the charge amplification coefficient is K _q ～ 1, while the power amplification coefficient is K _w ～ 13. When using the inductive-capacitive load, a similar nanotransistor could be an element of an integrated circuit—radiation generator with wavelength λ = 3–6 mm and specific power of ～10⁴ W/cm² with efficiency of ～85–90%.     

MBE HgCdTe Technology: A Very General Solution to IR Detection,Described by “Rule 07”, a Very Convenient Heuristic

“Rule 07,” a simple empirical relationship, conveniently estimates state- of-the-art HgCdTe dark current performance over 13 orders of magnitude, covering wavelength ranges form short-wave infrared (SWIR) to long-wave infrared (LWIR), from room temperature to liquid nitrogen temperatures. The best HgCdTe, in some cases, approaches the external radiative limit of performance, but is typically two to three orders of magnitude above that, being limited by defect generation centers as yet unidentified and/or by Auger mechanisms. The empirical relationship represents the range of detectors fabricated at Teledyne using our molecular beam epitaxy (MBE)-based double-layer planar heterostructure (DLPH) technology, but also appears to characterize good detectors from other laboratories.     

A Nano “Immune-Guide” Recruiting Lymphocytes and Modulating the Ratio of Macrophages from Different Origins to Enhance Cancer Immunotherapy

Artificially modulating the type, density, and location of immune cells within the tumor microenvironment can suppress tumor growth and efficiently promote current immunotherapy. In this study, a magnetite nanoparticle-based “immune-guide” is developed by the functionalization of magnetite nanoparticles with hyaluronic acid (HA). HA, an extracellular matrix component, can target various CD44-overexpressing tumors and mediate the adhesion and migration of multiple types of immune cells. Thus, HA-functionalized magnetite nanoparticles (HA-PDA@Fe₃O₄) can highly efficiently accumulate in breast cancer and penetrate deep into the tumor parenchyma. Consequently, high intratumoral concentration of HA, serving as a “guidepost,” can directly recruit lymphocytes and elicit more chemokine production through cascading amplification effects, turning the immune “cold” tumor into a “hot” one. More importantly, HA-PDA@Fe₃O₄ can effectively remodel the diversity, origin, and activation of tumor-associated macrophages by recruiting and activating infiltrating macrophages, while simultaneously reducing the M2-maintained tissue-resident macrophages. Thus, HA-PDA@Fe₃O₄ synergistically improves T cell- and macrophage-based immunotherapies as well as interferes with the formation of premetastatic niches in the lung. By redistributing the localization of HA in tumors by using magnetite nanoparticles, this study provides a unique strategy to modulate the tumor immune microenvironment and potentiate tumor immunotherapies by using biocompatible nanomaterials without any therapeutic drug.     

Answer to comments on “Fabrication and photovoltaic conversion enhancement of graphene/n-Si Schottky barrier solar cells by electrophoretic deposition”

Here, we reply to comments by Valentic et al. on our paper published in Electrochimica Acta (2014, 130: 279). They commented that Au nanoparticles played the dominant role on the whole cell''s performances in our improved graphene/Si solar cell. We argued that our devices are Au-doped graphene/n-Si Schottky barrier devices, not Au nanoparticles (film)/n-Si Schottky barrier devices. During the doping process, most of the Au nanopatricles covered the surfaces of the graphene. Schottky barriers between doped graphene and n-Si dominate the total cells properties. Through doping, by adjusting and tailoring the Fermi level of the graphene, the Fermi level of n-Si can be shifted down in the graphene/Si Schottky barrier cell. They also argued that the instability of our devices were related to variation in series resistance reduced at the beginning due to slightly lowered Fermi level and increased at the end by the self-compensation by deep in-diffusion of Au nanoparticles. But for our fabricated devices, we know that an oxide layer covered the Si surface, which makes it difficult for the Au ions to diffuse into the Si layer, due to the continuous growth of SiO₂ layer on the Si surface which resulted in series resistance decreasing at first and increasing in the end.