Rationally Tailoring Chiral Molecules to Minimize Interfacial Energy Loss Enables Efficient and Stable Perovskite Solar Cells Using Vacuum Flash Technology.

Facing the defects and energy barrier at the interface of perovskite solar cells, we propose a chiral molecule engineering strategy to simultaneously heal interfacial defects and regulate interfacial energy band alignment. S-ibuprofen (S-IBU), R-ibuprofen (R-IBU), and racemic ibuprofen (rac-IBU) are used to post-treat perovskite films. rac-IBU molecules possess the strongest anchoring on the surface of perovskites among all chiral molecules, translating into the best defect passivation effect. The hydrophobic isobutyl group and benzene ring could increase the film moisture resistance ability. Due to reduced interfacial defects and interfacial energy barrier, rac-IBU enables efficient devices with a maximum efficiency exceeding 24% based on vacuum flash technology without antisolvents. The encapsulated rac-IBU-modified device could maintain 90% of its initial performance after 1040 h of continuous maximum power point tracking. This work provides a feasible route to minimize interfacial nonradiative recombination losses by controlling spatial conformation via rational chiral molecule engineering.

Electromagnetic Response of Multistage-Helical Nano-Micro Conducting Polymer Structures and their Enhanced Attenuation Mechanism of Multiscale-Chiral Synergistic Effect.

Nowadays, the rapidly development of advanced antidetection technology raises stringent requirements for microwave absorption materials (MAMs) to focus more attention on wider bandwidth, thinner thickness, and lower density. Adding magnetic medium to realize broadband absorption may usually result in the decline of service performance and accelerating corrosion of MAMs. Chiral MAMs can produce extra magnetic loss without adding magnetic medium due to the unique electromagnetic cross polarization effect. However, more efforts should be taken to furtherly promote efficient bandwidth of chiral MAMs and reveal attenuation mode and modulation method of chiral structure. Herein, a novel superhelical nano-microstructure based on chiral polyaniline and helical polypyrrole is successfully achieved via in situ polymerization strategy. The enhanced multiscale-chiral synergistic effect contributes to broaden effective absorption bandwidth, covering 8.6 GHz at the thickness of 3.6 mm, and the minimum reflection loss can reach -51.3 dB simultaneously. Besides, to further explain response modes and loss mechanism of superhelical nano-microstructures, the electromagnetic simulation and test analysis are applied together to reveal their synergistic enhancement attenuation mechanism. Taken together, this strategy gives a new thought of how to design, prepare, and optimize the hierarchical structure materials to achieving broadband and high-performance microwave absorption.

Bionic structures for optimizing the design of stealth materials.

Traditional microwave absorbing materials (MAMs) have exposed more and more problems in multi-spectrum detection and a harsh service environment, which hinder their further application. Bionic materials and structures have attracted more and more attention from researchers in the field of stealth materials due to their excellent properties, such as high strength and high conductivity, along with easy access to scale adjustability and structural design. By introducing the concept of bionics into their structural design and material design, we can obtain highly efficient stealth materials with multiple properties. In addition, the concept of multispectral stealth is furthered by comparing the difference in the principle and methods of achievement between radar stealth and infrared stealth. This paper fundamentally summarizes the research status of bionic structure design ideas in stealth materials, analyzing the structure-activity relationship between the structural size effect and electromagnetic characteristics from low order to high order. Then, the design ideas and universal strategies of typical bionic structures are summarised and an idea for the integrated design of radar absorption compatible with infrared stealth is put forward. This will provide profound insights for the application of biomimetic stealth materials and the future development of intelligent-response and dynamically adjustable materials.

Insights into the mechanism underlying remediation of Cr(VI) contaminated aquifer using nanoscale zero-valent iron@reduced graphene oxide.

Currently, there is an urgent need to develop functional nanomaterials for highly effective environmental remediation. However, the long-term effect of remedial materials upon their injection into contaminated aquifer has frequently been overlooked. Here, the remediation of Cr(VI) contaminated aquifer by reduced graphene oxide (rGO) supported nanoscale zero-valent iron (nZVI@rGO) was investigated from a long-term perspective. The performances of nZVI@rGO samples with different rGO loadings in the removal of aqueous Cr(VI) were evaluated in batch experiments. The electron transfer properties different nZVI@rGO samples were investigated by measuring their corrosive potentials using the steady-state Tafel polarization curves. The results show that the electron transfer efficiency between Cr(VI) and nZVI@rGO is enhanced owing to the large reactive conjugated structure of rGO. Besides, the surface passivation of nZVI is effectively retarded due to the uniform accommodation of Cr(III) precipitates on rGO. The structure and composition of nZVI@rGO before and after Cr(VI) removal were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The characterization results revealed that most Cr(VI) ions (∼90%) will be reduced to Cr(III) precipitates on nZVI@rGO as the passivation product. Accordingly, Cr(VI) ions tend to react more readily at less blocked regions on the surface of rGO, and a layer-by-layer passivation model on nZVI@rGO surface is proposed. Our results provide new insights into the mechanism underlying the long-term remediation of Cr(VI) contaminated aquifer using nZVI@rGO, which helps design new materials and approaches for practical in-situ remediation engineering.

Functionalizing phenethylammonium by methoxy to achieve low-dimensional interface defects passivation for efficient and stable perovskite solar cells.

Low dimensional interface passivation has been proved to be an efficient method to lessen the nonradiative recombination loss in perovskite solar cells. To overcome the limitation of Phenethylammonium (PEA+) for carrier transport and water molecule intrusion, we developed a modification strategy by functioning the typical PEA+with the 4-methoxy to optimize the interface defects and carrier transport performance, thus maximizing the synchronous improvement of device efficiency and stability. Our results indicate that the 2 mg ml-14-methoxy-phenethylammonium (MeO-PEA+) modified device could achieve a best power conversion efficiency of 19.64% with improved shelf-life stability in ambient conditions. The new passivation molecule of MeO-PEA+could possess the capability of defect passivation, carrier transfer, and moisture blocking, demonstrating that rationally designed organic components for interface passivation could help to achieve efficient and stable PSCs.

Predicting atomic-level reaction mechanisms for SN2 reactions via machine learning.

Identifying atomic-level reaction mechanisms is an essential step in chemistry. In this study, we develop a joint-voting model based on three parallel machine-learning algorithms to predict atomic-level and dynamical mechanisms trained with 1700 trajectories. Three predictive experiments are carried out with the training trajectories divided into ten, seven, and five classes. The results indicate that, as the number of trajectories in each class increases from the ten- to five-class model, the five-class model converges the fastest and the prediction success rate increases. The number of trajectories in each experiment to get the predictive models converged is 100, 100, and 70, respectively. The prediction accuracy increases from 88.3% for the ten-class experiment, to 91.0% for the seven-class, and to 92.0% for the five-class. Our study demonstrates that machine learning can also be used to predict elementary dynamical processes of structural evolution along time, that is, atomic-level reaction mechanisms.

Morphology-controlled synthesis of boehmite with enhanced efficiency for the removal of aqueous Cr(VI) and nitrates.

Boehmite with different morphologies was synthesized using a simple hydrothermal method for the removal of Cr(VI) and nitrates from polluted water. When the pH of the hydrothermal system was changed, the final crystallization products had morphologies of one-dimensional rods or two-dimensional sheets with different sizes. The boehmites were characterized and used for the adsorption of aqueous Cr(VI) and nitrates. Their bulk structure and surface properties significantly changed with the corresponding morphology, which prominently affected their adsorption capacity. Boehmite with a 2D small sheet-like structure showed the highest adsorption capacity (64.7 mg g-1). Moreover, the small sheet-like boehmite showed a remarkable adsorption capacity towards nitrates (74.5-378.5 mg g-1) and maintained a high selectivity to Cr(VI) in the presence of competing anions such as NO3 -, [Formula: see text] and Cl-. The isotherms for Cr(VI) sorption could be better explained using the Langmuir model, indicating a monolayer adsorption of the Cr species, while the isotherms for nitrate sorption followed the Freundlich model, suggesting a multilayer adsorption. The active adsorption sites of boehmite were found to be the Lewis acid sites and surface hydroxyl groups according to the outcomes of the analysis using a series of characterization methods such as IR, Raman and x-ray photoelectron spectra. The unique structure of boehmite is beneficial to adsorb anion containments while maintaining a high selectivity to Cr(VI) species. Because of the multiple Lewis or Brönsted acid sites in boehmite, the Cr(VI) was reduced to less toxic Cr(III) species and immobilized on the surface of boehmite. In consideration of the low-cost and good regeneration capacity, the small sheet-like boehmite would be useful for the removal of anions present in polluted water.

Selenocysteine inhibits human osteosarcoma cells growth through triggering mitochondrial dysfunction and ROS-mediated p53 phosphorylation.

Osteosarcoma represents the most common primary malignant bone tumor in children and adolescents, which shows severe resistance toward standard chemotherapy because of high invasive capacity and growing incidence. Selenocysteine (SeC) is a naturally available Se-containing amino acid that displays splendid anticancer activities against several human tumors. However, little information about SeC-induced growth inhibition against human osteosarcoma is available. Herein, the anticancer efficiency and underlying mechanism of SeC against human osteosarcoma were evaluated in vitro and in vivo. The results revealed that SeC significantly inhibited MG-63 human osteosarcoma cells growth in vitro through induction of S-phase arrest and apoptosis, as reflected by the decrease of cyclin A and CDK-2, PARP cleavage, and caspases activation. SeC treatment also resulted in mitochondrial dysfunction through affecting Bcl-2 family expression. Moreover, SeC triggered p53 phosphorylation by inducing reactive oxygen species (ROS) overproduction. ROS inhibition effectively blocked SeC-induced cytotoxicity and p53 phosphorylation. Importantly, MG-63 human osteosarcoma xenograft growth in nude mice was significantly suppressed in vivo through triggering apoptosis and p53 phosphorylation. These results indicated that SeC had the potential to inhibit human osteosarcoma cells growth in vitro and in vivo through triggering mitochondrial dysfunction and ROS-mediated p53 phosphorylation, which validated the potential application of Se-containing compounds in treatment of human osteosarcoma.

Effects of the Long Non-Coding RNA HOST2 On the Proliferation, Migration, Invasion and Apoptosis of Human Osteosarcoma Cells.

BACKGROUND/AIMS: This study aimed to explore the effects of the long non-coding RNA HOST2 (lnc-HOST2) on the proliferation, migration, invasion and apoptosis of osteosarcoma cells. METHODS: Osteosarcoma tissues and adjacent normal tissues from 52 patients were selected. Human osteosarcoma cell lines (SaOS2, HOS, U2OS and MG-63) were collected and cultured; MG-63 cells had the highest lnc-HOST2 expression and thus were used in subsequent experiments. Then, MG-63 cells were transfected and divided into the blank (no transfection), si-CON (transfected with negative control siRNA) and si-lnc-HOST2 (transfected with small interference lnc-HOST2 siRNA) groups. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expression of lnc-HOST2 in primary tissues and cells. Cell growth was detected using the CCK-8 and colony formation assays. Cell doubling time was detected. Cell migration and invasion were observed using the scratch test and Transwell assays. Cell apoptosis and cell cycle progression of osteosarcoma cells were detected using flow cytometry with annexin V/PI double staining and PI staining, respectively. RESULTS: The level of lnc-HOST2 expression in the si-lnc-HOST2 group was significantly decreased compared to that in the blank and si-CON groups. The OD values in the si-lnc-HOST2 group were significantly lower than those in the blank and si-CON groups. Compared to the blank and si-CON groups, the si-lnc-HOST2 group presented significant decreases in the colony number and healing rates after scratching. The number of invasive cells in the si-lnc-HOST2 group was significantly less than that in the blank and si-CON groups. In the si-lnc-HOST2 group, the cell cycle was mainly halted in the G1 phase, and the apoptosis rate and doubling time in this group were significantly higher than those in the blank group and si-CON group. CONCLUSIONS: Inhibition of lnc-HOST2 could suppress the proliferation, migration, and invasion and promote the apoptosis of osteosarcoma cells.

Silencing of ATF2 inhibits growth of pancreatic cancer cells and enhances sensitivity to chemotherapy.

Pancreatic cancer is one of the leading causes of cancer-related death worldwide. Activating transcription factor 2 (ATF2) is a multifunctional transcription factor, and is implicated in tumor progress, yet its role in pancreatic cancer remains unclear. In the present study, the level of ATF2 in pancreatic cancer tissues and the adjacent non-tumorous tissues was detected by quantitative real-time PCR and Western blot. The roles of ATF2 in the proliferation, cell cycle, and apoptosis of pancreatic cancer cells were investigated through ATF2 silencing, and the effect of ATF2 shRNA on the sensitivity of pancreatic cancer cells to gemcitabine, an anti-tumor drug, was explored. The results of our study showed that the ATF2 level in the pancreatic cancer tissues was higher than that in the adjacent non-tumorous tissues. Silencing of ATF2 was found to inhibit proliferation, arrest cell cycle at G1 phase and induce apoptosis in pancreatic cancer cells. Moreover, ATF2 silencing enhanced gemcitabine-induced growth-inhibition and apoptosis-induction effects in pancreatic cancer cells. In summary, silencing of ATF2 inhibited the growth of pancreatic cancer cells and enhanced the anti-tumor effects of gemcitabine, suggesting that ATF2 plays a pro-survival role in pancreatic cancer. Our results also propose that a high level of ATF2 may serve as a potential biomarker of pancreatic cancer, and that ATF2 may become a potential target for anti-tumor therapy.

Design of porous C@Fe3O4 hybrid nanotubes with excellent microwave absorption.

An efficient method was developed to fabricate a porous hybridizing nanotubes structure of amorphous carbon interspersed among Fe3O4 (C@Fe3O4) with a ∼200 nm diameter and ∼70 nm wall thickness. The as-structured porous nanotubes with ferromagnetic behaviour exhibited excellent microwave absorption properties, including a strong ability to attenuate the electromagnetic (EM) wave, and they are also lightweight. Adding only 10 wt% of the as-prepared sample into paraffin can show a maximum reflection loss of -45.0 dB at 6.18 GHz with a sample thickness of 3.4 mm. The absorption mechanism, which results from its porous nanotubes structure, multi-interfaces, dielectric-magnetic integration and geometric effect, is proposed to explain the excellent EM absorption performance. Furthermore, the synthesis strategy presented herein can be expended as a facile approach to synthesizing related carbon-based nanostructures for functional design and applications.

MicroRNA-150 Inhibits Cell Invasion and Migration and Is Downregulated in Human Osteosarcoma.

miR-150 expression in osteosarcoma (OS) cell lines and human osteoblast cells was detected, and OS cell models were transfected with exogenous miR-150 to investigate its role in cell proliferation, invasion, and apoptosis. Our results showed that miR-150 expression in OS cells (MG63, Saos-2, SOSP-9607, and U2OS) was significantly lower compared to the osteoblast hFOB1.19 cell line (all p < 0.01). The expression level of miR-150 in MG63 cells that were transfected with exogenous miR-150 mimics was markedly upregulated, while the miR-150 expression level in the inhibitor group was significantly downregulated (both p < 0.01). Similar results were also found in SOSP-9607 cells. Importantly, exogenous miR-150 expression stimulated cell apoptosis and inhibited proliferation, invasion, and migration. A luciferase reporter assay displayed that miR-150 also regulated Sp1 expression by targeting its 3'-UTR, and qRT-PCR and Western blotting showed that elevated levels of miR-150 may reduce Sp1 protein expression. The mRNA and protein levels of Sp1 were upregulated after transfection with a Sp1-expression plasmid and partially reversed the inhibitory effects of miR-150 on cell proliferation, invasion, and metastasis in MG63 and SOSP-9607 cells, as well as promoted cell apoptosis. In conclusion, miR-150 inhibits cell proliferation, invasion, and metastasis and stimulates cell apoptosis by regulating the expression of Sp1. Therefore, miR-150 may be a potential clinical target for the treatment of OS patients.

Energy efficiency in surmounting the central energy barrier: a quantum dynamics study of the OH + CH3 → O + CH4 reaction.

The present quantum dynamics study of the OH + CH3 shows that, for this "central" (slightly early) barrier reaction, it is the vibrational energy of the reactant OH that is more effective in promoting the reactivity than the translational energy; while previous studies show that, for its forward reaction O + CH4 also with a "central" (slightly late) barrier, it is the translational energy that is more effective in surmounting the energy barrier than the vibrational energy. Since both barriers deviate only slightly from the center of the potential energy surface, these findings indicate that for these two reactions with more-or-less central barriers, a small change of the barrier location can greatly affect which energy form determines the reaction reactivity. This study also shows that both the rotational excitation states of OH and CH3 hinder the reactivity.

Interaction between pancreatic cancer cells and tumor-associated macrophages promotes the invasion of pancreatic cancer cells and the differentiation and migration of macrophages.

In this study, the impact of pancreatic cancer cell interaction with macrophages on the differentiation and function of macrophages and the behaviors of pancreatic cancer cells in vitro is evaluated. The expression of immunocompetent cell-associated markers in 22 pancreatic cancer specimens was characterized by immunohistochemistry. The impact of pancreatic cancer cells (PANC-1 and BxPC-3) on the differentiation and migration of human U937 monocytes and the effect of U937-derived macrophages on the proliferation and invasion of PANC-1 and BxPC-3 were determined by transwell assays. The potential effect on U937-derived macrophages or on the behaviors of pancreatic cancer cells following coculture in a transwell system was analyzed by quantitative real-time polymerase chain reaction. The high levels of macrophage-related CD68 and CD163 expression were detected in the pancreatic cancer specimens. Pancreatic cancer cells promoted the differentiation of U937 cells and migration of U937-derived macrophages, but decreased the mRNA transcripts of macrophage polarization-related genes of interleukin (IL)-10, IL-12p40, inducible nitric oxide synthase (iNOS), and CD163, particularly for iNOS. Furthermore, U937-derived M2 macrophages inhibited the proliferation of pancreatic cancer cells, but promoted their invasion. Coculture of pancreatic cancer cells with U937-derived macrophages upregulated the mRNA expression of genes associated with the epithelial-mesenchymal transition process, angiogenesis, and stemness of pancreatic cancer, but downregulated the expression of E-cadherin in pancreatic cancer cells. The interaction between pancreatic cancer cells and tumor-associated macrophages may play a pivotal role in the progression of pancreatic cancer.

[Differential concentrations of conjugated bile acids in sera of patients with polypoid lesions of gallbladder].

OBJECTIVE: To explore the concentration differences of eight conjugated bile acids between patients of cholesterol polyps and adenomatous polyps and determine the differential diagnosis markers for polypoid lesions of gallbladder (PLG). METHODS: During the period of March 2013 to November, 18 cholesterol polyps patients, 9 adenomatous polyps ones and 20 simple gallstone disease ones were enrolled. High performance liquid chromatography with ultraviolet detection was used to test 8 conjugated bile acids in sera. RESULTS: A total of 8 conjugated bile acids were completely dissociated within 10 minutes and the assay was liner in the range of 3.91 to 500.00 mg/L. The correlation coefficients for linear regression were from 0.995 to 0.999 and the detection limits ranged from 3.91 to 7.81 mg/L. The serum level of glycocholic acid (GCA) in adenomatous polyps group (3.48 ± 1.66) mg/L was significantly higher than that in cholesterol polyps group ((2.16 ± 0.71) mg/L, q = 5.182, P = 0.001) and control group ((2.15 ± 0.45) mg/L, q = 5.313, P = 0.001). The serum level of glycochenodeoxycholic acid (GCDCA) in adenomatous polyps group (12.67 ± 1.74) mg/L was significantly higher than that in cholesterol polyps group ((10.53 ± 3.04) mg/L, q = 3.253, P = 0.026) and control group ((10.72 ± 1.58) mg/L, q = 3.015, P = 0.038). The serum level of taurochenodeoxycholic acid (TCDCA) in adenomatous polyps group ((6.79 ± 2.90) mg/L) was significantly higher than that in cholesterol polyps group ((4.47 ± 2.35) mg/L, q = 3.412, P = 0.020) and control group ((4.72 ± 2.11) mg/L q = 3.091, P = 0.034). CONCLUSION: The serum levels of GCA, GCDCA and TCDCA in adenomatous polyps patients are higher than those in cholesterol polyps counterparts. And these markers may aid the differential diagnosis of PLG.

Role of microsurgical techniques combined with Ilizarov techniques in limb salvage and functional reconstruction of thermal­crush injuries of the hand: A case report.

The Ilizarov technology was proposed by Former Soviet orthopedic physician Ilizarov. It is a medical method to reconstruct missing tissues. Ilizarov technology combined with soft tissue stretching technology is of great significance in the treatment of common orthopedic problems like bone defects, finger absence, joint contracture and joint stiffness following thermal-crush injuries of the hand. In the present study a 25-year-old male patient sought for limb salvage treatment 1 month after sustaining thermal-crush injuries of the right hand and forearm. The patient had been treated by another hospital with multiple procedures of debridement, and recommended for forearm amputation. The patient was diagnosed with: i) Postoperative infection of thermal-crush injuries of the right hand and right forearm; ii) comminuted open fractures of the proximal and distal phalanges of the right thumb; iii) osteomyelitis; iv) palm skin defects with exposed tendons; and v) skin defects of the opisthenar and the forearm. After a series of treatments including debridement, removal of necrotic tissue, tissue transplantation, skin pedicle, bone lengthening, external shaping, tissue release, joint fusion, traction and rehabilitation exercises, the patient recovered some hand function. Overall, thermal-crush injuries of the hand are severe, complicated combined injuries composed of both heat burn and compression injury and their treatment is challenging. Overall, microsurgery combined with Ilizarov technology can effectively reconstruct the function of complex thermal-crush injuries of the hand.

Replantation of multiple fingertip amputations using super microsurgery: A case report and literature review.

Background: The fingertip amputation is an amputation type of the finger beyond the proximal nail fold. There is no vein available for anastomoses on the dorsal side of the finger, and the palmar vein of the finger is small and tightly attached to the skin. Therefore, it is relatively difficult to implement surgical anastomoses, which poses challenges to the clinical treatment of fingertip amputations. Case report: A 29-year-old male was admitted to the hospital due to "the amputation of the fingertips of the right index, middle, and ring fingers caused by a heavy object compression 3 h ago". The admission examination revealed that the right index, middle, and ring fingers were completely severed at the 1/2 plane of the nail bed, with irregular sections, severe contusion, and pollution. The X-ray examination showed comminuted fractures of the distal phalanges of the right index, middle, and ring fingers. Based on these findings, the patient was diagnosed with multiple severed fingertips of the right hand (Tamai Zone 1). The patient underwent debridement, vascular exploration, and replantation of the right index, middle, and ring fingertips under emergency general anesthesia. After surgery, anti-inflammatory, spasmolytic, and anticoagulant treatment and regular dressing changes were conducted. The patient did not receive a blood transfusion, and all three fingers survived. The appearance of these fingers was favorable 3 months after surgery, and the flexion and extension of these fingers were normal. Eventually, the patient achieved excellent Chen's hand function scores. Conclusions: To the best of our knowledge, this may be the first successful case regarding the replantation of three fingertips after amputations in Tamai Zone 1 with favorable outcomes. It can be maintained that super microsurgery can be used for the replantation of multiple fingertip amputations.

Rational design of bimetallic MBene for efficient electrocatalytic nitrogen reduction.

Electrocatalytic nitrogen reduction reaction (NRR) is one of the most promising approaches to achieving green and efficient NH3 production. However, the designs of efficient NRR catalysts with high activity and selectivity still are severely hampered by inherent linear scaling relations among the adsorption energies of NRR intermediates. Herein, the properties of ten M3B4 type MBenes have been initially investigated for efficient N2 activation and reduction to NH3via first-principles calculations. We highlight that Cr3B4 MBene possesses remarkable NRR activity with a record-low limiting potential (-0.13 V). Then, this work proposes descriptor-based design principles that can effectively evaluate the catalytic activity of MBenes, which have been further employed to design bimetallic M2M'B4 MBenes. As a result, 5 promising candidates including Ti2YB4, V2YB4, V2MoB4, Nb2YB4, and Nb2CrB4 with excellent NRR performance have been extracted from 20 bimetallic MBenes. Further analysis illuminates that constructing bimetallic MBenes can selectively tune the adsorption strength of NHNH2** and NH2NH2**, and break the linear scaling relations between their adsorption energies, rendering them ideal for NRR. This work not only pioneers the application of MBenes as efficient NRR catalysts but also proposes rational design principles for boosting their catalytic performance.

Porous boron nitride with a high surface area: hydrogen storage and water treatment.

We report on the synthesis of high-quality microporous/mesoporous BN material via a facile two-step approach. An extremely high surface area of 1687 m(2) g(-1) and a large pore volume of 0.99 cm(3) g(-1) have been observed in the synthesized BN porous whiskers. The formation of the porous structure was attributed to the group elimination of organic species in a BN precursor, melamine diborate molecular crystal. This elimination method maintained the ordered pore structure and numerous structural defects. The features including high surface area, pore volume and structural defects make the BN whiskers highly suitable for hydrogen storage and wastewater treatment applications. We demonstrate excellent hydrogen uptake capacity of the BN whiskers with high weight adsorption up to 5.6% at room temperature and at the relatively low pressure of 3 MPa. Furthermore, the BN whiskers also exhibit excellent adsorption capacity of methyl orange and copper ions, with the maximum removal capacity of 298.3 and 373 mg g(-1) at 298 K, respectively.

Quantum dynamics study of vibrational excitation effects and energy requirement on reactivity for the O + CD4/CHD3 → OD/OH + CD3 reactions.

A quantum reactive dynamics, six-degrees-of-freedom, time-dependent wave packet method is employed to study vibrational enhancement and energy requirement on reactivity of the O((3)P) + CD4/CHD3 → OD/OH + CD3 reactions. The calculations show, for O + CD4, that all the vibrational excitations of CD4 enhance reactivity, which agrees with quasi-classical trajectory results. However, this finding contradicts the experimental observation where the bending excitation suppresses reactivity. The present study also reveals that translational energy, in general, is more effective to enhance reactivity than vibrational energy; however, at higher collision energy, vibrational energy is slightly more effective than translational energy. For O + CHD3, the stretching and bending excitations of CHD3 enhance the reaction, whereas the umbrella motion hinders reactivity. The calculated excitation functions agree well with experiments.