Soft-in-Rigid Strategy Promoting Rapid and High-Capacity Lithium Storage by Chemical Scissoring.

Large and rapid lithium storage is hugely demanded for high-energy/power lithium-ion batteries; however, it is difficult to achieve these two indicators simultaneously. Sn-based materials with a (de)alloying mechanism show low working potential and high theoretical capacity, but the huge volume expansion and particle agglomeration of Sn restrict cyclic stability and rate capability. Herein, a soft-in-rigid concept was proposed and achieved by chemical scissoring where a soft Sn-S bond was chosen as chemical tailor to break the Ti-S bond to obtain a loose stacking structure of 1D chain-like Sn1.2Ti0.8S3. The in situ and ex situ (micro)structural characterizations demonstrate that the Sn-S bonds are reduced into Sn domains and such Sn disperses in the rigid Ti-S framework, thus relieving the volume expansion and particle agglomeration by chemical and physical shielding. Benefiting from the merits of large-capacity Sn with an alloying mechanism and high-rate TiS2 with an intercalation mechanism, the Sn1.2Ti0.8S3 anode offers a high specific capacity of 963.2 mA h g-1 at 0.1 A g-1 after 100 cycles and a reversible capacity of 250 mA h g-1 at 10 A g-1 after 3900 cycles. Such a strategy realized by chemical tailoring at the structural unit level would broaden the prospects for constructing joint high-capacity and high-rate LIB anodes.

Pyrolysis Mechanism of Ionic Liquid Under Microwave Irradiation and the Formation of N-Doped Carbon.

The pyrolysis mechanism of the ionic liquid [BMIm]N(CN)2 under microwave irradiation was discussed for the first time. The trimerization of the anion N(CN)-2 and the formation of a framework were firstly caused by the microwave irradiation. And then the carbonization of the framework occurred when the temperature reached 330 °C. The pyrolysis product was graphitic nitrogendoped carbon and mainly originated from the anion N(CN)-2. The nitrogen content and graphitization degree of the nitrogen-doped carbon was relied on the pyrolysis temperature.

Insights into the discrepant luminescence for BaSiO3 :Eu2+ phosphors prepared by solid-state reaction and precipitation reaction methods.

Two synthesis routes, solid-state reaction and precipitation reaction, were employed to prepare BaSiO3 :Eu2+ phosphors in this study. Discrepancies in the luminescence green emission at 505 nm for the solid-state reaction method sample and in the yellow emission at 570 nm for the sample prepared by the precipitation reaction method, were observed respectively. A detail investigation about the discrepant luminescence of BaSiO3 :Eu2+ phosphors was performed by evaluation of X-ray diffraction (XRD), photoluminescence (PL)/photoluminescence excitation (PLE), decay time and thermal quenching properties. The results showed that the yellow emission was generated from the BaSiO3 :Eu2+ phosphor, while the green emission was ascribed to a small amount of Ba2 SiO4 :Eu2+ compound that was present in the solid-state reaction sample. This work clarifies the luminescence properties of Eu2+ ions in BaSiO3 and Ba2 SiO4 hosts.

Two-beam interferometer with optical path difference magnified.

A two-beam interferometer is proposed and experimentally demonstrated with OPD magnified. Two cascaded fiber ring resonators with almost the same fiber length are spliced into a fiber loop. An acousto-optic modulator is employed to generate optical pulses and to choose the pulses traveling around one of the resonators for x trips. The interferometer is characterized in displacement in our experiment. Experimental results show the proportional relationship between the sensitivity and x. The high-sensitivity interferometer scheme is useful in some measurement applications that require high sensitivity, such as solid earth tide gauge.

Accelerating ion/electron transport by engineering an indium-based heterostructure toward large and reversible lithium storage.

The high activity of the In2O3/In2S3 heterostructure can be activated into homogeneous In2OxS3-x nanodots, thereupon stabilizing the subsequent cycles. The In2O3/In2S3 can offer a high capacity of 1140 mA h g-1 at 0.1 A g-1 after 290 cycles, and even at 1 A g-1, it harvests a reversible capacity of 900 mA h g-1 after 600 cycles.

Improving the alkali metal electrode/inorganic solid electrolyte contact via room-temperature ultrasound solid welding.

The combination of alkali metal electrodes and solid-state electrolytes is considered a promising strategy to develop high-energy rechargeable batteries. However, the practical applications of these two components are hindered by the large interfacial resistance and growth of detrimental alkali metal depositions (e.g., dendrites) during cycling originated by the unsatisfactory electrode/solid electrolyte contact. To tackle these issues, we propose a room temperature ultrasound solid welding strategy to improve the contact between Na metal and Na3Zr2Si2PO12 (NZSP) inorganic solid electrolyte. Symmetrical Na|NZSP | Na cells assembled via ultrasonic welding show stable Na plating/stripping behavior at a current density of 0.2 mA cm-2 and a higher critical current density (i.e., 0.6 mA cm-2) and lower interfacial impedance than the symmetric cells assembled without the ultrasonic welding strategy. The beneficial effect of the ultrasound welding is also demonstrated in Na|NZSP | Na3V2(PO4)3 full coin cell configuration where 900 cycles at 0.1 mA cm-2 with a capacity retention of almost 90% can be achieved at room temperature.

Color tuning of direct white light of lanthanum aluminate with mixed-valence europium.

The generation of direct white-light emission of the coexisting valence-varied europium-lanthanum aluminate through substitution of cations into the host and its resultant adjustment of the energy transfer have been presented. With respect to La(0.99-x)Sr(x)AlO(3-delta):Eu(0.01) and La(0.994)Al(1-x)O(3-delta):Eu(0.006), and Mn(x), Li(0.012), the green-light emission positioned at 515 nm plays a key role to color mix for white light and can be efficiently tuned by adjusting the transfer of energy and relevant transition emissions between the luminous centers of Eu(2+) and Eu(3+)/Mn(2+), via varying amounts of dopants. Direct white-light emission with optimized values of 86 for the color rendering index and 5091 K for the correlated color temperature has been achieved for lanthanum aluminate by this mixed-valence means.

Response to comment on "Tunable thermal quenching properties of Na3Sc2(PO4)3:Eu2+ phosphors tailored by phase transformation details" by Z. Liu et al., Dalton Trans., 2020, 49, 3615.

Yan argues that our reported abnormal negative thermal quenching (TQ) of the Na3Sc2(PO4)3:Eu2+ phosphor was a pitfall caused by the diminishment in optical path lengths of the spectrofluorometer originating from the increasing volume of the phosphor at elevated temperatures. We disagree with this suggestion and affirm that the negative TQ was an intrinsic property of Na3Sc2(PO4)3:Eu2+ phosphor associated with the phase transformation during heating.

Tunable thermal quenching properties of Na3Sc2(PO4)3:Eu2+ phosphors tailored by phase transformation details.

Luminescence thermal quenching of phosphors is one of the prominent problems in restricting their application in high-power LED devices. In the current work, tunable luminescence thermal quenching behaviors, including abnormal negative thermal quenching and normal thermal quenching, were demonstrated for Na3Sc2(PO4)3:Eu2+ phosphors tailored by phase transformation details. A series of ionic substitution schemes were employed to synthesize α-, ß- and γ-Na3Sc2(PO4)3:Eu2+ phosphors, which show discrepant phase transformations during heating. The thermal event associated with phase transformation is perceived to be responsible for the observations of abnormal negative thermal quenching performances, in view of the suppression of non-radiative paths by consuming thermal energy during the phenomenon of phase transformation. Our results provide an insight into the relationship between the thermal quenching behaviors and phase transformation details of the Na3Sc2(PO4)3:Eu2+ phosphor and offer a useful clue to exploit high thermal stability phosphors.

Tunable single-doped single-host full-color-emitting LaAlO(3):Eu phosphor via valence state-controlled means.

A full-color-emitting phosphor of valence-varied Eu doped perovskite-type LaAlO(3) with the aid of energy transfer is demonstrated and its luminescence properties can be tuned through controllable addition of doped ions.

[Fluorescence studies of Eu ions adsorption on pseudo-boehmite colloidal particle surface].

Stable pseudo-boehmite sol was obtained by adding HNO3 as peptizing agent and adjusting pH to be 2.0. TEM result shows that the AlOOH colloidal particle size is about 60 nm. Field emission transmission electron microscope (FETEM) result shows that pseudo-boehmite colloidal particle is composed of 8 nm scaled AlOOH nanocrystals. The interaction of Eu3+ ions and colloidal AlOOH nanoparticle was investigated. The adsorption of Eu3+ ions on the surface of AlOOH nanocrystal was attributed to the chemical adsorption caused by electrostatic attraction. The photoluminescence characters of Eu3+ in AlOOH/Eu(NO3)3 composite sol system were investigated. The 529 nm emission intensity of Eu3+, I592, decreased with the increase in the molar ratio of AlOOH and Eu3+, RBoe/Re. The adsorption ratio (denoted R) and the adsorption density (denoted D) of Eu3+ ions on AlOOH colloidal particle surface was calculated from I592. The results show that the values of R and D increase with increasing RBoe/Re.

Novel g-C3N4/CoO Nanocomposites with Significantly Enhanced Visible-Light Photocatalytic Activity for H2 Evolution.

Novel g-C3N4/CoO nanocomposite application for photocatalytic H2 evolution were designed and fabricated for the first time in this work. The structure and morphology of g-C3N4/CoO were investigated by a wide range of characterization methods. The obtained g-C3N4/CoO composites exhibited more-efficient utilization of solar energy than pure g-C3N4 did, resulting in higher photocatalytic activity for H2 evolution. The optimum photoactivity in H2 evolution under visible-light irradiation for g-C3N4/CoO composites with a CoO mass content of 0.5 wt % (651.3 µmol h-1 g-1) was up to 3 times as high as that of pure g-C3N4 (220.16 µmol h-1 g-1). The remarkably increased photocatalytic performance of g-C3N4/CoO composites was mainly attributed to the synergistic effect of the junction or interface formed between g-C3N4 and CoO.

Nitrogen-Deficient Graphitic Carbon Nitride with Enhanced Performance for Lithium Ion Battery Anodes.

Graphitic carbon nitride (g-C3N4) behaving as a layered feature with graphite was indexed as a high-content nitrogen-doping carbon material, attracting increasing attention for application in energy storage devices. However, poor conductivity and resulting serious irreversible capacity loss were pronounced for g-C3N4 material due to its high nitrogen content. In this work, magnesiothermic denitriding technology is demonstrated to reduce the nitrogen content of g-C3N4 (especially graphitic nitrogen) for enhanced lithium storage properties as lithium ion battery anodes. The obtained nitrogen-deficient g-C3N4 (ND-g-C3N4) exhibits a thinner and more porous structure composed of an abundance of relatively low nitrogen doping wrinkled graphene nanosheets. A highly reversible lithium storage capacity of 2753 mAh/g was obtained after the 300th cycle with an enhanced cycling stability and rate capability. The presented nitrogen-deficient g-C3N4 with outstanding electrochemical performances may unambiguously promote the application of g-C3N4 materials in energy-storage devices.

Red/blue-shift dual-directional regulation of α-(Ca, Sr)2SiO4:Eu(2+) phosphors resulting from the incorporation content of Eu(2+)/Sr(2+) ions.

In this work, tunable emission from green to red and the inverse tuning from red to green in α-(Ca, Sr)2SiO4:Eu(2+) phosphors were demonstrated magically by varying the incorporation content of Eu(2+) and Sr(2+) ions, respectively. The tunable emission properties and the tuning mechanism of red-shift resulting from the Eu(2+) content as well as that of blue-shift induced by the Sr(2+) content were investigated in detail. As a result of fine-controlling the incorporation content of Eu(2+), the emission peak red-shifts from 541 nm to 640 nm. On the other hand, the emission peak inversely blue-shifts from 640 nm to 546 nm through fine-adjusting the incorporation content of Sr(2+). The excellent tuning characteristics for α-(Ca, Sr)2SiO4:Eu(2+) phosphors presented in this work exhibited their various application prospects in solid-state lighting combining with a blue chip or a near-UV chip.

Human leukocyte antigen-C and killer cell immunoglobulin-like receptor gene polymorphisms among patients with syphilis in a Chinese Han population.

Syphilis is a sexually transmitted infection caused by the Treponema pallidum subspecies pallidum spirochete bacterium. The killer cell immunoglobulin-like receptors (KIR), interacting with human leukocyte antigens (HLA), regulate the activations of natural killer (NK) cells and certain T-cell subsets in response to microbe infection. The objective of this study was to explore whether KIR and HLA-C gene polymorphisms were associated with syphilis in a Chinese Han population. Polymerase chain reaction with sequence-specific primers (PCR-SSP) method was used to genotype KIR and HLA-C genes in 231 syphilis patients and 247 healthy controls. Framework genes KIR2DL4, KIR3DL2, KIR3DL3 and KIR3DP1 were present in all individuals. The frequencies of KIR2DS3 and KIR3DS1 were higher in syphilis patients than in healthy controls (p = 0.030 and p = 0.038, respectively), while the frequency of KIR2DS5 was higher in healthy controls than in syphilis patients (p = 0.015; OR = 0.575). The homozygote for HLA-C1 allele (HLA-C1C1) was more common in controls compared with syphilis patients (p = 0.030; OR = 0.667). The frequency of individuals with HLA-C1C1 and KIR2DL3 genotype was higher in control group relative to syphilis patient group (p = 0.018; OR = 0.647). These data indicated that KIR2DS3 and KIR3DS1 were more prevalent in syphilis patients than in controls, and that KIR2DS5, HLA-C1C1 and HLA-C1C1-KIR2DL3 were more prevalent in controls than in syphilis patients, respectively. These will require further investigation using functional studies.

Fabrication of Densely Packed AlN Nanowires by a Chemical Conversion of Al(2)O(3) Nanowires Based on Porous Anodic Alumina Film.

Porous alumina film on aluminum with gel-like pore wall was prepared by a two-step anodization of aluminum, and the corresponding gel-like porous film was etched in diluted NaOH solution to produce alumina nanowires in the form of densely packed alignment. The resultant alumina nanowires were reacted with NH(3) and evaporated aluminum at an elevated temperature to be converted into densely packed aluminum nitride (AlN) nanowires. The AlN nanowires have a diameter of 15-20 nm larger than that of the alumina nanowires due to the supplement of the additional evaporated aluminum. The results suggest that it might be possible to prepare other aluminum compound nanowires through similar process.

[Clinical study of juvenile nasopharyngeal angiofibroma].

OBJECTIVE: To present our experiences of diagnosis and treatment for juvenile nasopharyngeal angiofibroma (JNA) and to evaluate the factors influencing intra-operative bleeding and tumor recurrence. METHOD: Forty-five patients suffered form JNA experienced surgical management and/or radiotherapy between January 1980 and December 2001 were studied retrospectively. All the patients were males. The age ranged from 13 to 24 years with mean of 16.3 years. Three operative approaches were selected according to tumor stage: the traditional and modified transpalatal, lateral rhinotomy and craniofacial combined approach. Six cases received postoperative radiotherapy and 1 case received radiotherapy without surgery. RESULT: The tumors were completely resected in 36 cases and recurred in 9 cases (20%) during a follow-up period of 6-84 months. Six of the 9 recurrent tumors were completely resected and the rest 3 were incompletely resected combined with postoperative radiotherapy. No recurrence was found in a follow-up period of 1-3 years. The tumor stage influences intraoperative bleeding and the incidence of recurrence. No statistically significance difference was found when comparing preoperative embolization of the vessels and ligature of the external carotid artery patients with non-embolized and control group (P = 0.554). CONCLUSION: (1) With the approaches of operation selected according to tumor stage, most of the tumors can be removed by the traditional/modified transpalatal and lateral rhinotomy approaches; (2) Preoperative ligature of the external carotid artery and embolization of the vessels feeding the tumor can not reduce intraoperative bleeding. The inconsistency of tumor staging in test and control groups may lead to this result; (3) The tumors stage influences the intraoperative bleeding and the incidence of recurrence; (4) Radiotherapy is an effective adjuvant treatment for the patients with advanced stage or recurrent tumors.