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1.
Mol Pain ; 20: 17448069241252384, 2024.
Article En | MEDLINE | ID: mdl-38631843

PD-1/PD-L1 inhibitors have been demonstrated to induce itch in both humans and experimental animals. However, whether the PD-1/PD-L1 pathway is involved in the regulation of chronic psoriatic itch remains unclear. This study aimed to investigate the role of the PD-1/PD-L1 pathway in imiquimod-induced chronic psoriatic itch. The intradermal injection of PD-L1 in the nape of neck significantly alleviated chronic psoriatic itch in imiquimod-treated skin. Additionally, we observed that spontaneous scratching behavior induced by imiquimod disappeared on day 21. Still, intradermal injection of PD-1/PD-L1 inhibitors could induce more spontaneous scratching for over a month, indicating that imiquimod-treated skin remained in an itch sensitization state after the spontaneous scratching behavior disappeared. During this period, there was a significant increase in PD-1 receptor expression in both the imiquimod-treated skin and the spinal dorsal horn in mice, accompanied by significant activation of microglia in the spinal dorsal horn. These findings suggest the potential involvement of the peripheral and central PD-1/PD-L1 pathways in regulating chronic itch and itch sensitization induced by imiquimod.


B7-H1 Antigen , Imiquimod , Programmed Cell Death 1 Receptor , Pruritus , Psoriasis , Animals , Imiquimod/pharmacology , Imiquimod/adverse effects , Pruritus/chemically induced , Pruritus/metabolism , Psoriasis/chemically induced , Psoriasis/complications , Psoriasis/metabolism , Programmed Cell Death 1 Receptor/metabolism , B7-H1 Antigen/metabolism , Male , Mice , Signal Transduction/drug effects , Skin/metabolism , Skin/pathology , Mice, Inbred C57BL , Chronic Disease
2.
Carbohydr Polym ; 316: 121060, 2023 Sep 15.
Article En | MEDLINE | ID: mdl-37321743

Multifunctional biomass-based aerogels with mechanically robust and high fire safety are urgently needed for the development of environmentally-friendly intelligent fire fighting but challenging. Herein, a novel polymethylsilsesquioxane (PMSQ)/cellulose/MXene composite aerogel (PCM) with superior comprehensive performance was fabricated by ice-induced assembly and in-situ mineralization. It exhibited light weight (16.2 mg·cm-3), excellent mechanical resilience, and rapidly recovered after being subjected to the pressure of 9000 times of its own weight. Moreover, PCM demonstrated outstanding thermal insulation, hydrophobicity and sensitive piezoresistive sensing. In addition, benefiting from the synergism of PMSQ and MXene, PCM displayed good flame retardancy and improved thermostability. The limiting oxygen index of PCM was higher than 45.0 %, and it quickly self-extinguished after being removed away from fire. More importantly, the rapid electrical resistance reduction of MXene at high temperature endowed PCM with sensitive fire-warning capability (trigger time was less than 1.8 s), which provided valuable time for people to evacuate and relief. This work provides new insights for the preparation and application of the next-generation high performance biomass-based aerogels.


Cellulose , Organosilicon Compounds , Humans , Biomass
3.
J Integr Neurosci ; 22(3): 64, 2023 May 08.
Article En | MEDLINE | ID: mdl-37258427

BACKGROUND: Apigenin has been reported to exhibit anti-inflammatory and anti-oxidative activities. This study aimed to investigate the protective role of Apigenin on chemotherapy-induced peripheral neuropathy (CIPN). METHODS: CIPN mouse model was established using Paclitaxel treatment. Hot plate and tail prick latency tests were performed to examine the allodynia and hyperalgesia behaviors. Anti-inflammatory and anti-oxidative effects of Apigenin on CIPN were determined by enzyme-linked immunosorbent (ELISA) assay, Western blot, and qRT-PCR. Nuclear recruitment of nuclear factor erythroid 2-related factor 2 (NRF2) was analyzed to evaluate the underlying mechanisms of the protective effects of Apigenin. RESULTS: Apigenin significantly alleviated CIPN-induced nociceptive behaviors of CIPN mice. It also decreased the TNF-α and IL-1ß levels, suppressed oxidative stress and inflammation in the surgical spinal cord tissues. Mechanistically, Apigenin altered the pro-inflammatory and anti-inflammatory phenotypes ratio of microglia through promoting the nuclear recruitment of NRF2 and activating the NRF2/Antioxidant Response Element (ARE) signaling pathway. CONCLUSIONS: In summary, Apigenin relieves CIPN by regulating microglia activation and polarization, which provides a potential therapeutic strategy for CIPN treatment.


Antineoplastic Agents , Peripheral Nervous System Diseases , Mice , Animals , Hyperalgesia/chemically induced , Hyperalgesia/drug therapy , Hyperalgesia/metabolism , Apigenin/pharmacology , Apigenin/metabolism , Apigenin/therapeutic use , Microglia , NF-E2-Related Factor 2/metabolism , Peripheral Nervous System Diseases/chemically induced , Peripheral Nervous System Diseases/drug therapy , Anti-Inflammatory Agents/adverse effects , Antineoplastic Agents/pharmacology
4.
Am J Transl Res ; 15(3): 1667-1679, 2023.
Article En | MEDLINE | ID: mdl-37056861

OBJECTIVE: To investigate the effect of energy intake restriction on postoperative cognitive dysfunction (POCD) after internal fixation of tibial fractures in mice. METHODS: Thirty mice were divided into model groups of internal fixation of tibial fractures with 0%, 20%, 30% and 40% energy intake restriction and sham operation group (n = 6). Novel object recognition task and elevated plus maze test were used to assess the ability of recognition memory and anxiety-related behavior before and one week after surgery. The blood samples were collected from mice on days 1, 3 and 7 after surgery, and the mice were euthanized on the 8th day after surgery. RT-PCR and Western blot were employed to detect the expression of AMPK-SIRT1 pathway-related genes and proteins in the hippocampus. ELISA was used to detect the levels of inflammatory factors in the peripheral blood of mice. Hematoxylin-eosin (H&E) staining and immunofluorescence (IF) staining were used to detect the proliferation, differentiation and injury of hippocampal cells. RESULTS: The results showed that 20% and 30% energy intake restriction significantly improved the POCD after internal fixation of tibial fractures in mice. Significantly, 30% energy intake restriction reduced the expression of AP-1, NF-κB, CD45, IBA-1, and inflammatory factors IL-1ß, IL-6, IL-8 and TNF-α, and increased the expression of AMPK and SIRT1 after the operation. H&E and IF staining showed that 30% energy intake restriction reduced postoperative hippocampal neuronal damage. CONCLUSION: Energy intake restriction can significantly improve POCD after internal fixation of tibial fractures in mice and may provide a new treatment paradigm for POCD patients.

5.
Pain Ther ; 11(3): 923-935, 2022 Sep.
Article En | MEDLINE | ID: mdl-35674985

INTRODUCTION: Pain management for older patients with hip fractures is challenging. This study aimed to investigate the effect of ultrasound-guided fascia iliac compartment block (UGFICB) using different doses of nalbuphine in combination with ropivacaine on preoperative analgesia in older patients with hip fractures. METHODS: In this multicenter randomized controlled trial, 280 elderly patients with hip fracture were randomly allocated into four UGFICB groups (n = 70 in each group): a ropivacaine group (30 mL 0.1% ropivacaine + 0.9% normal saline) and three ropivacaine plus nalbuphine groups (5, 10, and 20 mg nalbuphine, respectively). The primary outcomes were the duration of analgesia at rest and on passive movement. Secondary outcomes included sensory block area, side effects, and vital signs. The doses of rescue analgesia with parecoxib sodium were also analyzed. RESULTS: The addition of nalbuphine dose-dependently increased the duration of analgesia at rest and on passive movement (P < 0.05) and expanded the area of sensory block (P < 0.05). Compared with the ropivacaine group, the pain scores at rest and on movement at 6 and 8 h after the block were lower in three ropivacaine plus nalbuphine groups (P < 0.05), without between-group differences at 2, 4, and 12 h. The four groups had comparable side effects (nausea and vomiting) and vital signs (P > 0.05). CONCLUSIONS: UGFICB with 5, 10, and 20 mg nalbuphine added to ropivacaine prolonged the analgesia duration, increased sensory block area, reduced pain, and decreased the doses of rescue parecoxib sodium for older patients after hip fracture, without obvious side effects. Among these three doses, nalbuphine 20 mg in combination with ropivacaine provided the longest duration of analgesia and the largest sensory block area. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2000029934).

6.
ACS Appl Mater Interfaces ; 13(19): 23020-23029, 2021 May 19.
Article En | MEDLINE | ID: mdl-33949192

Multifunctional intelligent fireproof cotton fabrics are urgently demanded in the era of the Internet of Things. Herein, a novel high fire safety cotton fabric (denoted as MXene/CCS@CF) with temperature sensing, fire-warning, piezoresistivity, and Joule heating performance was developed by coating MXene nanosheet and carboxymethyl chitosan (CCS) via an eco-friendly layer-by-layer assembly method. Benefiting from the thermoelectric characteristic and high conductivity of MXene nanosheet, MXene/CCS@CF exhibited accurate wide-range temperature sensing performance. When being burned, it could repeatedly trigger the fire-warning system in less than 10 s. More importantly, MXene/CCS@CF showed outstanding flame retardancy because of the synergistic carbonization between MXene and CCS. The limiting oxygen index of MXene/CCS@CF was as high as 45.5%, and the char length was only 33 mm after the vertical burning test. Meanwhile, its peak heat release rate reduced more than 66%. Besides, the obtained fabric could detect a variety of human motions. Moreover, the controllable Joule heating performance enabled the fabric to be used in extreme cold weather. This work provides a facile approach to fabricating a next-generation high fire safety cotton fabric, showing promising applications in firefighting, home automation, and smart transportation.

7.
Front Public Health ; 9: 617521, 2021.
Article En | MEDLINE | ID: mdl-33869125

Background: Fine air pollutant particles have been reported to be associated with risk of preeclampsia. The association between air pollutant exposure and preeclampsia risk in heavily air polluted Taiwan warrants investigation. Methods: We combined data from Taiwan National Health Insurance (NHI) Research Database (NHIRD) and Taiwan Air Quality Monitoring Database. Women aged 16-55 years were followed from January 1, 2000, until appearance of ICD-9 coding of preeclampsia withdrawal from the NHI program, or December 31, 2013. Daily concentration of NOx, NO, NO2, and CO was calculated by Kriging method. The Cox proportional hazard regression model was used for risk assessment. Results: For NOx, Relative to Quartile [Q] 1 concentrations, the Q2 (adjusted hazard ratio adjusted = 2.20, 95% CI = 1.50-3.22), Q3 (aHR = 7.28, 95% CI = 4.78-11.0), and Q4 (aHR = 23.7, 95% CI = 13.7-41.1) concentrations were associated with a significantly higher preeclampsia or eclampsia risk. Similarly, for NO, relative to Q1 concentrations, the Q2 (aHR = 1.82, 95% CI = 1.26-2.63), Q3 (aHR = 7.53, 95% CI = 5.12-11.0), and Q4 (aHR = 11.1, 95% CI = 6.72-18.3) concentrations were correlated with significantly higher preeclampsia or eclampsia risk. Furthermore, for NO2, relative to Q1 concentration, the Q2 (aHR = 1.99, 95% CI = 1.37-2.90), Q3 (aHR = 6.15, 95% CI = 3.95-9.57), and Q4 (aHR = 32.7, 95% CI = 19.7-54.3) concentrations also associated with a significantly higher preeclampsia or eclampsia risk. Conclusion: Women exposed to higher NOX, NO, NO2, and CO concentrations demonstrated higher preeclampsia incidence.


Air Pollutants , Pre-Eclampsia , Adolescent , Adult , Air Pollutants/adverse effects , Cohort Studies , Female , Gases , Humans , Middle Aged , Pre-Eclampsia/epidemiology , Pregnancy , Taiwan/epidemiology , Young Adult
8.
Clin Neuropharmacol ; 43(5): 134-138, 2020.
Article En | MEDLINE | ID: mdl-32947423

OBJECTIVE: Nalbuphine and dexmedetomidine are both used as anesthesia adjuvants for brachial plexus block, but their efficacy and safety in younger patients are not clear. In this study, we aimed to compare the efficacy and side effects of these 2 drugs in young patients undergoing brachial plexus block. METHODS: We recruited 48 young patients aged 18 to 30 years requiring supraclavicular brachial plexus block. Subjects were randomly divided into 2 groups. Patients in group levobupivacaine+nalbuphine received 28 mL of 0.5% levobupivacaine and 10 mg of nalbuphine diluted in 2 mL 0.9% saline. Patients in group levobupivacaine+dexmedetomidine (LD) received 28 mL of 0.5% levobupivacaine and 0.75 µg/kg dexmedetomidine diluted in 2 mL 0.9% saline. Demographic information, types of fracture, onset time of motor and sensory blocks, duration of block, side effects, and analgesic use were recorded. RESULTS: We found that the 2 groups did not differ significantly in the demographic profile and fracture type. Compared with group LD, group LD had significantly shorter sensory and motor block onset time, longer block duration, less analgesic need, and less side effects. CONCLUSION: In summary, our study suggests that nalbuphine is a better anesthesia adjuvant for supraclavicular brachial plexus block in young patients.


Brachial Plexus Block/methods , Dexmedetomidine , Hypnotics and Sedatives , Nalbuphine , Adolescent , Adult , Anesthetics, Local , Dexmedetomidine/adverse effects , Double-Blind Method , Female , Fractures, Bone/surgery , Humans , Hypnotics and Sedatives/adverse effects , Levobupivacaine , Male , Nalbuphine/adverse effects , Nerve Block , Pain, Postoperative/drug therapy , Pain, Postoperative/epidemiology , Postoperative Nausea and Vomiting/epidemiology , Prospective Studies , Young Adult
9.
Inorg Chem ; 59(3): 1883-1892, 2020 Feb 03.
Article En | MEDLINE | ID: mdl-31935070

A significant number of molecular catalysts have been developed for electrochemical CO2 reduction with high efficiency and selectivity; however, testing of these electrocatalysts in an application-ready system is lacking. Here, we present an example of a nonaqueous flow cell electrolyzer with [Ni(cyclam)]2+ as the homogeneous electrocatalyst for CO2 reduction. Using ferrocene as a sacrificial electron donor and ammonium salts as both electrolyte and proton donor, efficient catalytic CO2 reduction is achieved. The nonaqueous design shows high selectivity for the reduction of CO2 to CO (>80%) and achieves high current densities with a graphite felt working electrode (up to 50 mA·cm-2 with 0.5 M proton donor in MeCN solution), producing >40 mL·h-1 of CO. The choice of a molecular electrocatalyst, solvent, and proton donor are the key factors for achieving high activity with an efficient flow electrolyzer and the eventual development of a viable continuous process.

10.
Dalton Trans ; 48(26): 9454-9468, 2019 Jul 02.
Article En | MEDLINE | ID: mdl-31020284

Electrocatalytic CO2 reduction is of continued interest to sustainable energy research. Mononuclear transition metal complexes from Group 6 to Group 10 with a select subset of ligand frameworks have been demonstrated to be efficient electrochemical CO2 reduction catalysts. Here, we review the known mononuclear complexes from Group 6 to Group 10, examining trends in activity, electronic structure of catalytic intermediates, and product selectivity. The correlation between differences in electronic structure and CO2 reduction activity between these metal centers are discussed.

11.
Pharmacology ; 103(5-6): 324-332, 2019.
Article En | MEDLINE | ID: mdl-30943499

BACKGROUND/AIMS: Brachial plexus avulsion (BPA) generally causes a chronic persistent pain that lacks efficacious treatment. Curcumin has been found to possess anti-inflammatory abilities. However, little is known about the mechanisms and effects of curcumin in an animal model of BPA. METHODS: Mechanical withdrawal thresholds (MWT) were examined by von Frey filaments. Cold allodynia was tested by the acetone spray test. The levels of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in rat spinal cords were analyzed by the enzyme-linked immunosorbent assay, and the expression levels of c-Fos and nerve growth factor (NGF) were measured by Western blot. The expression level of glial fibrillary acidic protein (GFAP) was observed by immunofluorescence and Western blot. RESULTS: After curcumin treatment, the MWT showed a significant increase when compared to the BPA group on both hind paws. A remarkable decrease of paw-withdrawal response frequency was observed compared with the BPA group. In addition, curcumin treatment significantly decreased the levels of TNF-α and IL-6 in rat spinal cords that were exceedingly upregulated in the BPA group. The protein levels of c-Fos and NGF were decreased by treatment with curcumin compared with the corresponding protein levels in the BPA group. Besides, curcumin reduced the number of GFAP positive cells and GFAP expression. CONCLUSIONS: Our findings suggest that curcumin significantly extenuates the BPA-induced pain and inflammation by reducing the expression level of proinflammatory cytokines and pain-associated proteins and inhibiting the activity of astrocytes.


Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Brachial Plexus Neuropathies/drug therapy , Curcumin/pharmacology , Inflammation/drug therapy , Animals , Astrocytes/metabolism , Blotting, Western , Brachial Plexus/injuries , Brachial Plexus Neuropathies/physiopathology , Cytokines/metabolism , Disease Models, Animal , Fluorescent Antibody Technique , Glial Fibrillary Acidic Protein/metabolism , Inflammation/pathology , Interleukin-6/metabolism , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/metabolism
12.
Phytother Res ; 33(4): 1095-1103, 2019 Apr.
Article En | MEDLINE | ID: mdl-30740801

The aim of this study was to investigate whether ginsenoside Rf can effectively relieve pain hypersensitivity in a neuropathic pain rat model. Neuropathic pain was induced in rats by chronic constriction injury (CCI) to the right sciatic nerve. Ginsenoside Rf was administered intraperitoneally after CCI surgery. The von Frey filament test and forced swimming test were performed to examine pain hypersensitivity and depression-like behavior in rats. Western blot was used to measure the levels of inflammatory cytokines in the dorsal root ganglion (DRG) and the spinal cord. Pretreatment of ginsenoside Rf for 7 days did not affect the onset of mechanical allodynia in CCI rats; however, a single dose of ginsenoside Rf 1 day after surgery attenuated established mechanical allodynia in CCI rats. Additionally, chronic treatment of ginsenoside Rf 1 week before and 2 weeks after CCI surgery diminished mechanical allodynia and depression-like behavior without affecting spontaneous locomotor activity in CCI rats. Furthermore, in CCI rats, chronic ginsenoside Rf treatment partially reversed the upregulation of proinflammatory cytokines in the spinal cord and/or the DRG but elevated IL-10, an anti-inflammatory factor, in the DRG. Ginsenoside Rf alleviated neuropathic pain and its associated depression and restored the balance between proinflammatory and anti-inflammatory cytokines. Our results suggest that ginsenoside Rf may be a potential therapy for nerve injury-induced neuropathic pain.


Depression/drug therapy , Drugs, Chinese Herbal/therapeutic use , Ginsenosides/therapeutic use , Inflammation/drug therapy , Neuralgia/drug therapy , Wounds and Injuries/drug therapy , Animals , Chronic Disease , Drugs, Chinese Herbal/pharmacology , Ginsenosides/pharmacology , Male , Rats , Rats, Sprague-Dawley
13.
Neurosci Lett ; 687: 49-54, 2018 11 20.
Article En | MEDLINE | ID: mdl-30236878

Hydromorphone has been shown to play protective effect in rat glial cell. However, whether hydromorphone plays important roles in ischemia-reperfusion (IR) injury and the involved signaling pathway remains unclear. In this study, we detected whether HM plays protective effect in IR injury mouse model, further followed by the mechanism exploration. Preconditioning with hydromorphone was performed for continuous 4 days at the doe of 2 mg/kg before IR injury induction. Intraperitoneal injection of rapamycin (Rapa) was administrated to examine the role of mTOR in IR injury. The mRNA expression level was detected by RT-PCR, and protein expression level was detected by western blot. Latency time and apoptosis of hippocampal CA1 neurons were detected 72 h after IR injury induction. Preconditioning with hydromorphone significantly increased Latency time, decreased apoptosis of hippocampal CA1 neurons and suppressed IR induced oxidative stress. Mechanically, preconditioning with hydromorphone increased Bcl-2 and p-mTOR expression levels and decreased Bax expression levels. Rapa administration reverses the role of hydromorphone in protecting hippocampal CA1 neurons from IR injury. Hydromorphone protect hippocampal CA1 neurons from IR injury via activating mTOR signaling pathway.


Analgesics, Opioid/administration & dosage , CA1 Region, Hippocampal/metabolism , Hydromorphone/administration & dosage , Neuroprotective Agents/administration & dosage , Signal Transduction/physiology , TOR Serine-Threonine Kinases/metabolism , Animals , CA1 Region, Hippocampal/drug effects , Injections, Subcutaneous , Male , Mice , Mice, Inbred BALB C , Oxidative Stress/drug effects , Oxidative Stress/physiology , Signal Transduction/drug effects
14.
Inorg Chem ; 56(16): 9660-9668, 2017 Aug 21.
Article En | MEDLINE | ID: mdl-28783352

The interligand charge dynamics of the lowest singlet metal-to-ligand charge-transfer states (1MLCT S1 states) of a series of quadruply bonded trans-Mo2(NN)2(O2C-X)2 paddlewheel compounds are investigated, where NN is a π-accepting phenylpropiolamidinate ligand and O2C-X (X = Me, tBu, TiPB, or CF3) is an auxiliary carboxylate ligand. The compounds show strong light absorption in the visible region due to MLCT transitions from the Mo2 center to the NN ligands. The transferred electron density was followed by femtosecond time-resolved infrared (fs-TRIR) spectroscopy with vibrational reporters such as the ethynyl groups on the NN ligands. The observed fs-TRIR spectra show that these compounds have asymmetric 1MLCT S1 excited states where the transferred electron mainly resides on a single NN ligand. The presence of interligand electron transfer (ILET) is suggested to explain the shape of the ν(C≡C) bands and the influence of auxiliary ligands and solvents on the interligand electronic coupling. The ILET in the 1MLCT S1 state is shown to be sensitive to the functional groups on the auxiliary ligands while being less responsive to changes in solvents.

15.
Arch Gerontol Geriatr ; 73: 29-36, 2017 Nov.
Article En | MEDLINE | ID: mdl-28743056

PURPOSE OF THE RESEARCH: Post operational cognitive dysfunction (POCD) occurs in patients after anesthesia and surgery. Abnormal histone acetylation and neuroinflammation are key factors in the pathogenesis of cognitive impairment. Apigenin not only has an anti-inflammatory activity but also modifies histone acetylation. We aimed to investigate whether apigenin can attenuate isoflurane exposure-induced cognitive decline by regulating histone acetylation and inflammatory signaling. MATERIALS AND METHODS: Spatial learning and memory were assessed by Morris water maze test. Levels of histone acetylation, BDNF and downstream signaling, and inflammatory components were analyzed. PRINCIPAL RESULTS: Isoflurane exposure in aged rats lead to impaired spatial learning and memory. These rats exhibited dysregulated histone H3K9 and H4K12 acetylation, which was accompanied by reduced BDNF expression and suppressed BDNF downstream signaling pathway. Apigenin restored histone acetylation and BDNF signaling. Apigenin also suppressed isoflurane exposure induced upregulation of proinflammatory cytokines and NFκB signaling pathway. MAJOR CONCLUSIONS: Memory impairment induced by isoflurane exposure is associated with dysregulated histone acetylation in the hippocampus, which affects BDNF expression and hence BDNF downstream signaling pathway. Apigenin recovers cognitive function by restoring histone acetylation and suppressing neuroinflammation.


Apigenin/pharmacology , Cognitive Dysfunction/chemically induced , Cognitive Dysfunction/metabolism , Epigenesis, Genetic , Hippocampus/drug effects , Hippocampus/metabolism , Histones/metabolism , Isoflurane/adverse effects , Acetylation , Animals , Cognition , Cognition Disorders/complications , Cognitive Dysfunction/pathology , Hippocampus/growth & development , Humans , Isoflurane/toxicity , Male , Memory Disorders/pathology , Rats , Rats, Sprague-Dawley
16.
Inorg Chem ; 56(3): 1433-1445, 2017 Feb 06.
Article En | MEDLINE | ID: mdl-28075120

Four photophysically interesting dimolybdenum paddlewheel compounds are synthesized and characterized: I and II contain amide ligand (N,3-diphenyl-2-propynamide), and III and IV contain thioamide ligand (N,3-diphenyl-2-propynethioamide). I and III are trans-Mo2L2(O2C-TiPB)2-type compounds, and II and IV are Mo2L4-type compounds, where O2C-TiPB is 2,4,6-triisopropylbenzoate. I-IV display strong light absorption due to metal to ligand charge transfer (MLCT) transitions from molybdenum to the amide/thioamide ligands. Charge transfer dynamics in the MLCT excited states of I-IV have been examined using femtosecond transient absorption (fs-TA) spectroscopy and femtosecond time-resolved infrared (fs-TRIR) spectroscopy. The asymmetric amide/thioamide ligands show two forms of regioarrangements in the paddlewheel compounds. Analyses of the ν(C≡C) bands in the fs-TRIR spectra of I and II show similar electron density distribution over ligands in their 1MLCT S1 states where only two amide ligands are involved and the transferred electron is mainly localized on one of them. The fs-TRIR spectra of III and IV, however, show different charge distribution patterns where the transferred electron is fully delocalized over two thioamide ligands in III and partially delocalized in IV. Fast interligand electron transfer (ILET) was recognized as the explanation for the various charge distribution patterns, and ILET was shown to be influenced by both the ligands and the ligand arrangements.

17.
Inorg Chem ; 55(12): 5836-44, 2016 Jun 20.
Article En | MEDLINE | ID: mdl-27249173

Two dimolybdenum compounds featuring amidinate ligands with a C≡C bond, Mo2(NN)4 (I), where NN = N,N'-diphenylphenylpropiolamidinate, and trans-Mo2(NN)2(T(i)PB)2 (II), where T(i)PB = 2,4,6-triisopropylbenzoate, have been prepared and structurally characterized by single-crystal X-ray crystallography. Together with Mo2(DAniF)4 (III), where DAniF = N,N'-bis(p-anisyl)formamidinate, all three compounds have been studied with steady-state UV-vis, IR, and time-resolved spectroscopy methods. I and II display intense metal to ligand charge transfer (MLCT). Singlet state (S1) lifetimes of I-III are determined to be 0.7, 19.1, and 2.0 ps, respectively. All three compounds have long-lived triplet state (T1) lifetimes around 100 µs. In femtosecond time-resolved infrared (fs-TRIR) experiments, one ν(C≡C) band is observed at the S1 state for I but two for II, which indicate different patterns of charge distribution. The electron would have to be localized on one NN ligand in I and partially delocalized over two NN ligands in II to account for the observations. The result is a standard showcase of excited-state mixed valence in coordination compounds.

18.
Appl Opt ; 55(9): 2331-8, 2016 03 20.
Article En | MEDLINE | ID: mdl-27140570

Capacitive touch panels (CTPs), as a medium of information interactions, have become essential parts in many consumer electronics. However, current methods such as image edge matching and frequency notch filter cannot suit the defect detection for the new-type complex CTP patterns, which have neither basic primitives nor periodicity. For solving the issues, we proposed a nonnegative matrix factorization (NMF)-based large-size image registration method, and combined it with image tolerance models to detect defects in such CTP patterns. The NMF-based image registration method can fast extract each CTP from a large image. And then, any three of registered images are selected as reference images, which are further processed by threshold processing and simple mathematical morphological operation to obtain tolerance models. Afterward, we can use the tolerance models to obtain a nondefective template. In the normal inspection stage, the defects in CTP patterns can be identified as long as comparing the tolerance models of the template and sensed images. The experimental results show that the proposed method can efficiently and accurately detect various types of defects in CTP patterns. Moreover, the detection results are robust under different illuminations. Therefore, this algorithm can be reliably applied in actual inspection of such new-type CTP patterns.

19.
ACS Nano ; 7(3): 2406-12, 2013 Mar 26.
Article En | MEDLINE | ID: mdl-23414527

Large-scale assembly of graphenes in a well-controlled macroscopic fashion is important for practical applications. We have developed a facile and straightforward approach for continuous fabrication of neat, morphology-defined, graphene-based hollow fibers (HFs) via a coaxial two-capillary spinning strategy. With a high throughput, HFs and necklace-like HFs of graphene oxide have been well-controlled produced with the ease of functionalization and conversion to graphene HFs via simply thermal or chemical reduction. This work paves the way toward the mass production of graphene-based HFs with desirable functionalities and morphologies for many of important applications in fluidics, catalysis, purification, separation, and sensing.

20.
Adv Mater ; 25(4): 591-5, 2013 Jan 25.
Article En | MEDLINE | ID: mdl-23081662

Deformation-tolerant devices are vital for the development of high-tech electronics of unconventional forms. In this study, a highly compressible supercapacitor has been fabricated by using newly developed polypyrrole-mediated graphene foam as electrode. The assembled supercapacitor performs based on the unique and robust foam electrodes achieves superb compression tolerance without significant variation of capacitances under long-term compressive loading and unloading processes.

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