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1.
J Am Chem Soc ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39026175

ABSTRACT

Cobalt (Co) is a promising candidate to replace noble metals in the hydrogenation process, which is widely employed in the chemical industry. Although the catalytic performance for this reaction has been considered to be significantly dependent on the Co crystal phase, no satisfactory systematic studies have been conducted, because it is difficult to synthesize metal nanoparticles that have different crystalline structures with similar sizes. Here we report a new method for the synthesis of cobalt nanoparticles using hydrosilane as a reducing agent (hydrosilane-assisted method). This new method uses 1,3-butanediol and propylene glycol to successfully prepare fcc and hcp cobalt nanoparticles, respectively. These two types of Co nanoparticles have similar sizes and surface areas. The hcp Co nanoparticles exhibit higher catalytic performance than fcc nanoparticles for the hydrogenation of benzonitrile under mild conditions. The present hcp Co catalyst is also effective for highly selective benzyl amine production from benzonitrile without ammonia addition, whereas many catalytic systems require ammonia addition for selective benzyl amine production. Mechanistic studies revealed that the fast formation of the primary amine and the prevention of condensation and secondary amine hydrogenation promote selective benzonitrile hydrogenation for benzylamine over hcp Co nanoparticles.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124712, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38950476

ABSTRACT

In this study, a series of tetraphenylethene-containing gold(I) complexes with different auxiliary ligands have been synthesized. These complexes were characterized using a variety of techniques including nuclear magnetic resonance spectroscopy, mass spectrometry, and single crystal X-ray diffraction. Their aggregation-induced emission (AIE) behaviors were investigated through ultraviolet/visible and photoluminescence spectrum analyses, and dynamic light scattering measurements. Meanwhile, their mechanofluorochromic properties were also studied via solid-state photoluminescence spectroscopy. Intriguingly, all these mononuclear gold(I) molecules functionalized by tetraphenylethene group demonstrated AIE phenomena. Furthermore, five gold(I) complexes possessing diverse auxiliary ligands exhibited distinct fluorescence changes in response to mechanical grinding. For luminogens 2-5, their solids showed reversible mechanofluorochromic behaviors triggered by the mutual transformation of crystalline and amorphous states, while for luminogen 1, blue-green-cyan three-color solid fluorescence conversion was realized by sequential mechanical grinding and solvent fumigation. Based on this stimuli-responsive tricolored fluorescence feature of 1, an information encryption system was successfully constructed.

3.
Sci Adv ; 10(7): eadk5444, 2024 02 16.
Article in English | MEDLINE | ID: mdl-38363838

ABSTRACT

Achieving high-contrast tricolor emissive regulation of a single-component molecule using a single type of external stimulus is highly desirable but challenging. In the present study, we report a symmetric acceptor-donor-acceptor (A-D-A)-type aggregation-induced emission-active luminogen, which displays a sequential high-contrast fluorescence switching just by anisotropic mechanical grinding. Specifically, upon light grinding, an orange-yellow-to-blue hypsochromic mechanofluorochromic response with a distinct color contrast (change in the maximum emission wavelength, Δλem,max = 122 nm) is noticed, and the slightly ground solid exhibits a blue-to-red high-contrast (Δλem,max = 185 nm) bathochromic mechanofluorochromic conversion upon vigorous grinding. Thus, using a single luminogen developed here, we can realize wide-range (Δλem,max > 100 nm) hypso- and bathochromic fluorescence mechanochromisms simultaneously. The tricolored mechanofluorochromic phenomenon is attributed to two different morphological transitions involving crystalline-to-crystalline and crystalline-to-amorphous states. Furthermore, three information anticounterfeiting systems are developed using the luminogen presented here.

4.
Chemistry ; 29(11): e202300242, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36744429

ABSTRACT

Invited for the cover of this issue are Zhao Chen at Jiangxi Science and Technology Normal University and Yue Sun at Tiangong University. For this cover picture, yellow ball containing character "D" represents donor, green ball containing character "A" represents acceptor. The image depicts eight donor-donor-acceptor-type carbazole derivatives that display full-color emission, and a luminogen that shows red to near-infrared mechano-fluorochromism and a photodynamic therapy effect. Read the full text of the article at 10.1002/chem.202203797.

5.
Chemistry ; 29(11): e202203797, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36545826

ABSTRACT

The preparation of multifunctionalized luminophores with full-color emission based on an identical core skeleton is a significative but challenging research topic. In this work, eight donor-donor-acceptor (D-D-A)-type luminogens based on a central carbazole core bearing a C6 hydrocarbon chain were designed by using different kinds of donor and acceptor units on the left and right, and synthesized in good yields. These D-D-A carbazole derivatives display deep-blue, sky-blue, cyan, green, yellow-green, yellow, orange and red fluorescence in the solid state, achieving full-color emission covering the whole visible light range under UV light illumination. Notably, the dicyano-functionalized triphenylamine-containing carbazole derivative exhibits rare aggregation-induced near-infrared emission and red-to-near-infrared mechano-fluorochromism with high contrast beyond 100 nm. Furthermore, the red-emissive luminogen can serve as a potential candidate for cell imaging and photodynamic therapy (PDT). This work not only provides reference for the construction of full-color emissive systems but also opens a new avenue to the preparation of multifunctionalized luminophores capable of simultaneous application in near-Infrared mechanical-force sensors and PDT fields.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 274: 121122, 2022 Jun 05.
Article in English | MEDLINE | ID: mdl-35290941

ABSTRACT

Mechanochromic luminophors with strong solid-state emission are promising candidates for high-contrast mechanochromic luminescence materials. Meanwhile, mechanically responsive luminogenic molecules with tricolor switching are highly desirable but are seldom reported. In this work, three anthracene-based donor-acceptor-π-donor (D-A-π-D) type benzothiadiazole derivatives were designed and synthesized. These luminogens showed remarkable aggregation-induced emission (AIE) or aggregation-induced emission enhancement (AIEE) effect. Furthermore, these luminogens exhibited bright and different solid state fluorescence involving yellow-green, yellow and orange colors, and the fluorescence of their solids could be effectively regulated by mechanical grinding. For luminogen 1, its solid displayed reversible two-color mechanofluorochromic property. As for luminogens 2 and 3, their solids displayed fluorescent colors change from yellow to yellow-green upon slight grinding, and the yellow-green light-emitting solids were converted into orange fluorescent solids after heavy grinding, demonstrating interesting three-color mechanofluorochromism features.


Subject(s)
Luminescence , Thiadiazoles , Spectrometry, Fluorescence
8.
Front Chem ; 9: 811294, 2021.
Article in English | MEDLINE | ID: mdl-35155382

ABSTRACT

A tetraphenylethene (TPE)-modified rhodanine derivative was successfully designed and prepared, and this luminophor showed intramolecular charge transfer nature from the TPE unit to the rhodanine-3-acetic acid unit. Interestingly, this luminogen not only exhibited typical aggregation-induced emission enhancement (AIEE) behavior but also showed good cell imaging performance. Remarkably, this AIEE-active TPE-containing rhodanine derivative possessed noticeable solvatochromic fluorescence effect involving multiple fluorescent colors of green, yellow-green, yellow, orange, and red. Meanwhile, this fluorescigenic compound displayed reversible mechanochromic fluorescence behavior based on the mutual transformation of between stable crystalline and metastable amorphous states. On the other hand, this multifunctional fluorophor could selectively and sensitively detect Hg2+ in an acetonitrile solution. Furthermore, this chemosensor could also be used to detect Hg2+ on test paper strips.

9.
World J Clin Cases ; 8(20): 4753-4762, 2020 Oct 26.
Article in English | MEDLINE | ID: mdl-33195643

ABSTRACT

BACKGROUND: Horseshoe kidney (HK) with renal stones is challenging for urologists. Although both retroperitoneal and transperitoneal laparoscopic approaches have been reported in some case reports, the therapeutic outcome of retroperitoneal compared with transperitoneal laparoscopic lithotripsy is unknown. AIM: To assess the efficacy of laparoscopic lithotripsy for renal stones in patients with HK. METHODS: This was a retrospective study of 12 patients with HK and a limited number (n ≤ 3) of 20-40 mm renal stones treated with either retroperitoneal or transperitoneal laparoscopic lithotripsy (June 2012 to May 2019). The perioperative data of both groups were compared including operation time, estimated blood loss, postoperative fasting time, perioperative complications and stone-free rate (SFR). RESULTS: No significant difference was observed for age, gender, preoperative symptoms, body mass index, preoperative infection, hydronephrosis degree, largest stone diameter, stone number and isthmus thickness. The mean postoperative fasting time of the patients in the retroperitoneal group and the transperitoneal group was 1.29 ± 0.49 and 2.40 ± 0.89 d, respectively (P = 0.019). There was no significant difference in operation time (194.29 ± 102.48 min vs 151.40 ± 39.54 min, P = 0.399), estimated blood loss (48.57 ± 31.85 mL vs 72.00 ± 41.47 mL, P = 0.292) and length of hospital stay (12.14 ± 2.61 d vs 12.40 ± 3.21 d, P = 0.881) between the retroperitoneal and transperitoneal groups. All patients in both groups had a complete SFR and postoperative renal function was within the normal range. The change in estimated glomerular filtration rate (eGFR) from the preoperative stage to postoperative day 1 in the retroperitoneal group and the transperitoneal group was -3.86 ± 0.69 and -2.20 ± 2.17 mL/(min·1.73 m2), respectively (P = 0.176). From the preoperative stage to the 3-mo follow-up, the absolute change in eGFR values for patients in the retroperitoneal group and the transperitoneal group was -3.29 ± 1.11 and -2.40 ± 2.07 mL/(min·1.73 m2), respectively (P = 0.581). CONCLUSION: Both retroperitoneal and transperitoneal laparoscopic lithotripsy seem to be safe and effective for HK patients with a limited number of 20-40 mm renal stones.

10.
RSC Adv ; 8(6): 3014-3023, 2018 Jan 12.
Article in English | MEDLINE | ID: mdl-35541203

ABSTRACT

Highly active metal nanoparticle (MNP) supported cellulose nanofiber (CNF) composites (Au/CNF, Ni/CNF and Ag/CNF) were prepared for the reduction of 4- and 2-nitrophenols (4-NP and 2-NP) in water. Transmission electron microscopy (TEM) images showed that the ultrafine nanoparticles (Au, Ni and Ag NPs) were uniformly deposited on CNFs surface. The content of Au (9.7 wt%), Ni (21.5 wt%) and Ag (22.6 wt%) in Au/CNF, Ni/CNF and Ag/CNF respectively was determined by energy dispersive spectroscopy (EDS) and inductive coupled plasma-mass spectroscopy (ICP-MS) analysis. The chemical state of the MNPs in Au/CNF, Ni/CNF and Ag/CNF was determined by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The significant metal-support interaction was studied by means of XPS. The Au/CNF, Ni/CNF and Ag/CNF demonstrated excellent catalytic activity towards the reduction of nitrophenols to aminophenols in water. To our delight, even a very low amount of catalyst was also found to be good enough to achieve 100% reduction of 4- and 2-NP with a higher reaction rate (within 5 min). The best rate constant (k app) values were determined for the cellulose nanocomposites. To the best our knowledge, Au/CNF, Ni/CNF and Ag/CNF are the most efficient nanocatalysts for the reduction of 4- and 2-NP reported to date. The catalytic performance of Au/CNF, Ni/CNF and Ag/CNF was compared with previously reported results. A possible mechanism has been proposed for these catalytic systems.

11.
Neural Regen Res ; 10(9): 1516-22, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26604915

ABSTRACT

Hypoxia promotes proliferation and differentiation of neural stem cells from embryonic day 12 rat brain tissue, but the concentration and time of hypoxic preconditioning are controversial. To address this, we cultured neural stem cells isolated from embryonic day 14 rat cerebral cortex in 5% and 10% oxygen in vitro. MTT assay, neurosphere number, and immunofluorescent staining found that 5% or 10% oxygen preconditioning for 72 hours improved neural stem cell viability and proliferation. With prolonged hypoxic duration (120 hours), the proportion of apoptotic cells increased. Thus, 5% oxygen preconditioning for 72 hours promotes neural stem cell proliferation and neuronal differentiation. Our findings indicate that the optimal concentration and duration of hypoxic preconditioning for promoting proliferation and differentiation of neural stem cells from the cerebral cortex are 5% oxygen for 72 hours.

12.
Article in Chinese | MEDLINE | ID: mdl-22932147

ABSTRACT

OBJECTIVE: To explore and evaluate the application of epiglottis with sternohyoid muscle in the surgery for laryngeal cancer. METHODS: Two fifty patients with laryngeal cancer were treated by partial laryngectomy and the laryngeal defects were reconstructed by epiglottic flap and sternohyoid muscle fascia flap. The staging of tumors: T2N0M0 23 cases, T3N1M0 14 cases, T3N2M0 13 cases. All of them received post radical radiotherapy with average 60 Gy. The patients were followed up for 3 to 5 years. Thirty patients underwent neck dissection. RESULTS: The three and five years survival rates were 90% and 80% respectively. The total cases eat breath pronounced well. The decannulation rate was 96%. CONCLUSION: After partial laryngectomy in laryngeal cancer epiglottic flap and sternohyoid muscle fascia flap were performed reconstruction of laryngeal function.


Subject(s)
Carcinoma, Squamous Cell/surgery , Epiglottis/transplantation , Laryngeal Neoplasms/surgery , Muscle, Skeletal/transplantation , Plastic Surgery Procedures/methods , Aged , Female , Humans , Hyoid Bone , Male , Middle Aged , Retrospective Studies , Sternum , Surgical Flaps
13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-316628

ABSTRACT

<p><b>OBJECTIVE</b>To explore and evaluate the application of epiglottis with sternohyoid muscle in the surgery for laryngeal cancer.</p><p><b>METHODS</b>Two fifty patients with laryngeal cancer were treated by partial laryngectomy and the laryngeal defects were reconstructed by epiglottic flap and sternohyoid muscle fascia flap. The staging of tumors: T2N0M0 23 cases, T3N1M0 14 cases, T3N2M0 13 cases. All of them received post radical radiotherapy with average 60 Gy. The patients were followed up for 3 to 5 years. Thirty patients underwent neck dissection.</p><p><b>RESULTS</b>The three and five years survival rates were 90% and 80% respectively. The total cases eat breath pronounced well. The decannulation rate was 96%.</p><p><b>CONCLUSION</b>After partial laryngectomy in laryngeal cancer epiglottic flap and sternohyoid muscle fascia flap were performed reconstruction of laryngeal function.</p>


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Carcinoma, Squamous Cell , General Surgery , Epiglottis , Transplantation , Hyoid Bone , Laryngeal Neoplasms , General Surgery , Muscle, Skeletal , Transplantation , Plastic Surgery Procedures , Methods , Retrospective Studies , Sternum , Surgical Flaps
14.
Br J Oral Maxillofac Surg ; 46(7): 554-60, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18539372

ABSTRACT

The aim of this study was to measure and analyse morphological data about the upper lips of healthy children in Chengdu, Western China. The characteristics and patterns of growth and development of the upper lip may be helpful in guiding the treatment of cleft lip. A total of 1500 healthy children aged between 2 and 12 were divided into 11 groups according to their age. Seven points on the upper lip were measured directly: the length from the alar base to the commissure, the length of the philtrum, the length from the tip of the Cupid's bow to the commissure, the width of one limb of the Cupid's bow, the length from the alar base to the central columella, the area of the unilateral upper lip, and the angle of the line of the alar base to the commissure and the line of the tip of the Cupid's bow to the commissure. Five aspects were significantly different among the groups: the length from the alar base to the commissure (p=0.04), the length from the tip of the Cupid's bow to the commissure (p=0.02), the width of the upper lip (p=0.02), the area adjacent to the lip (p=0.03), and the area of the unilateral upper lip (p=0.04). These data may be useful for reference to cleft lip repair.


Subject(s)
Cephalometry , Lip/anatomy & histology , Age Factors , Child , Child, Preschool , China , Ethnicity , Female , Humans , Lip/growth & development , Male , Nasal Cartilages/anatomy & histology
15.
J Craniofac Surg ; 17(1): 68-79, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16432411

ABSTRACT

Cleft palate is a congenital deformity with soft tissue and hard tissue defects. Normal cleft palate repairing surgery only repairs soft tissue defects, whereas bone defects in the hard palate still exist. Therefore, we conducted this study in beagles to observe the influence of bone grafting at primary surgery on craniofacial growth and occlusal relationships in individuals with complete cleft palate and to provide experimental evidence for optimal surgical procedures for cleft palate. Using 60 beagle puppies as subjects, we tested the effects of bone grafting in surgically induced palatal defect. The animals were randomly and equally divided into four groups: (1) unoperated controls; (2) surgically induced unilateral cleft palate, not repaired; (3) two-flap palatoplasty used to close the soft defect of the surgically induced cleft palate; (4) autogenous bone (a piece of rib bone) implanted into the palatal defect before two-flap palatoplasty was performed.Cephalometric roentgenography and plaster casts of the maxillary were taken preoperatively and every 4 weeks after surgery. Sixty metric cranial variables were measured directly from the cleaned skulls after the animals were killed the 34th week postoperatively. The measurement results indicated that bone grafting may reduce the disturbance of maxillary growth caused by the cleft palate and the denuded bone, but it may cause other maxillary deformities. This finding suggests that surgeons should be careful in choosing the method of primary bone grafting in repairing complete cleft palate.


Subject(s)
Bone Transplantation/methods , Cleft Palate/surgery , Dental Occlusion , Maxilla/growth & development , Animals , Cephalometry , Dental Arch/growth & development , Dental Arch/pathology , Disease Models, Animal , Dogs , Female , Male , Maxilla/pathology , Maxilla/surgery , Maxillofacial Development/physiology , Nose/pathology , Palate, Hard/surgery , Periosteum/surgery , Random Allocation , Plastic Surgery Procedures , Ribs , Surgical Flaps , Time Factors
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