Non-centrosymmetric metal chalcogenides such as AgGaS
2
and AgGaSe
2
are two of the commercial nonlinear optical (NLO) crystals widely used in the infrared (IR) region. Nevertheless, the inherent ...incompatibility between the wide energy gap (
E
g
) and large second-harmonic generation (SHG) efficiency (
d
ij
) hinders their high-power laser applications. Recently, the development of salt-inclusion chalcogenides with non-centrosymmetric structures has attracted more and more attention and interest owing to their intensive potential applications originating from their wide
E
g
, strong
d
ij
, ultrahigh laser-induced damage thresholds (LIDTs) and large IR transmission range. In this frontier paper, we review the recent progress of salt-inclusion chalcogenides (including 28 related compounds) as favourable candidates for IR-NLO materials, which can be divided into 3 types according to their chemical compositions and structural characteristics: (i) the R
a
X
b
Ga
n
Q
2
n
type and its derivatives, (ii) NaBa
4
ClGe
3
S
10
and its derivatives, and (iii) the A
3
XMB
12
(MQ
4
)
3
type. The relationships between the non-centrosymmetric structures and NLO properties of these 3 types of compounds are summarized and briefly remarked. In addition, the present challenges of creating new IR-NLO salt-inclusion chalcogenides and future perspectives in this field are discussed.
This frontier article discusses the recent progress and challenges of non-centrosymmetric (NCS) salt-inclusion chalcogenides (SICs) in the infrared nonlinear optical (IR NLO) field.
A novel turn-on fluorescence probe L has been designed that exhibits high selectivity and sensitivity with a detection limit of 9.53 × 10−8 mol/L for the quantification of Zn2+. 1H-NMR spectroscopy ...and single crystal X-ray diffraction analysis revealed the unsymmetrical nature of the structure of the Schiff base probe L. An emission titration experiment in the presence of different molar fractions of Zn2+ was used to perform a Job’s plot analysis. The results showed that the stoichiometric ratio of the complex formed by L and Zn2+ was 1:1. Moreover, the molecular structure of the mononuclear Cu complex reveals one ligand L coordinates with one Cu atom in the asymmetric unit. On adding CuCl2 to the ZnCl2/L system, a Cu-Zn complex was formed and a strong quenching behavior was observed, which inferred that the Cu2+ displaced Zn2+ to coordinate with the imine nitrogen atoms and hydroxyl oxygen atoms of probe L.
Metal-organic frameworks (MOFs) are excellent supports for metal nanoparticles (NPs), but the interactions between metal NPs and inorganic nodes of MOFs are weak because of the presence of organic ...ligands. Here, we present a strategy for strengthening the metal-NP/MOF interactions through controlled deligandation of the metal/MOF composites by thermal transformation. The controlled deligandation of MOF results in the formation of a “quasi-MOF,” which has a transition-state structure between the porous MOF and metal oxide. The obtained metal/quasi-MOF composites not only retain a porous structure but also achieve a strong interaction between the metal NPs (i.e., Au) and the inorganic nodes (i.e., Cr–O) of the quasi-MOF, leading to dramatically enhanced catalytic performance in the low-temperature oxidation of carbon monoxide (CO). The present findings could open new avenues for the design of superior heterogeneous catalysts.
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•“Quasi-MOF” created by controlled deligandation•Strong interaction and synergetic effect between guest metal NPs and inorganic nodes•Au/quasi-MIL-101 represents a benchmark in low-temperature CO oxidation
Low-temperature CO oxidation is increasingly important in relation to cleaning air and lowering automotive emissions. Metal-oxide-supported Au nanoparticle (NP) catalysts are commonly used for CO oxidation. The key to effective CO oxidation is the design of catalysts featuring high porosity and strong metal-support interactions. Metal-organic frameworks (MOFs) with high surface areas offer a potential platform for the design of promising catalysts, but their inorganic nodes are partitioned by organic ligands and show weak interaction with the guest metal NPs. Here, we demonstrate a general strategy for the fabrication of a “quasi-MOF” to realize both a porous structure and a strong interaction with a synergetic effect between the immobilized metal NPs and the inorganic nodes. The metal NP/quasi-MOF composite exhibits high catalytic activity in low-temperature CO oxidation.
“Quasi-MOFs” realize both an open-framework structure and a strong interaction with the guest metal nanoparticles (NPs). Through controlled deligandation of metal-NP/MOF composites, metal-NP/quasi-MOF composites can be fabricated, leading to dramatically enhanced catalytic performance.
Pancreatic ductal adenocarcinoma (PDAC) is a leading causes of cancer mortality worldwide. Currently, laparoscopic pancreatic resection (LPR) is extensively applied to treat benign and low-grade ...diseases related to the pancreas. The viability and safety of LPR for PDAC needs to be understood better. Laparoscopic distal pancreatectomy (LDP) and pancreaticoduodenectomy (LPD) are the two main surgical approaches for PDAC. We performed separate propensity score matching (PSM) analyses to assess the surgical and oncological outcomes of LPR for PDAC by comparing LDP with open distal pancreatectomy (ODP) as well as LPD with open pancreaticoduodenectomy (OPD).
We assessed the data of patients who underwent distal pancreatectomy (DP) and pancreaticoduodenectomy (PD) for PDAC between January 2004 and February 2020 at our hospital. A one-to-one PSM was applied to prevent selection bias by accounting for factors such as age, sex, body mass index, and tumour size. The DP group included 86 LDP patients and 86 ODP patients, whereas the PD group included 101 LPD patients and 101 OPD patients. Baseline characteristics, intraoperative effects, postoperative recovery, and survival outcomes were compared.
Compared to ODP, LDP was associated with shorter operative time, lesser blood loss, and similar overall morbidity. Of the 101 patients who underwent LPD, 10 patients (9.9%) required conversion to laparotomy. The short-term surgical advantage of LPD is not as apparent as that of LDP due to conversions. Compared with OPD, LPD was associated with longer operative time, lesser blood loss, and similar overall morbidity. For oncological and survival outcomes, there were no significant differences in tumour size, R0 resection rate, and tumour stage in both the DP and PD subgroups. However, laparoscopic procedures appear to have an advantage over open surgery in terms of retrieved lymph nodes (DP subgroup: 14.4 ± 5.2 vs. 11.7 ± 5.1, p = 0.03; PD subgroup 21.9 ± 6.6 vs. 18.9 ± 5.4, p = 0.07). These two groups did not show a significant difference in the pattern of recurrence and overall survival rate.
Laparoscopic DP and PD are feasible and oncologically safe procedures for PDAC, with similar postoperative outcomes and long-term survival among patients who underwent open surgery.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Sulfonyl fluorides are useful building blocks in a wide array of fields. Herein, we report a catalytic decarboxylative fluorosulfonylation approach for converting abundant aliphatic carboxylic acids ...to the corresponding sulfonyl fluorides. This transformation is enabled by simple preactivation as aldoxime esters and energy-transfer-mediated photocatalysis. This operationally simple method proceeds with high functional-group tolerance under mild and redox-neutral conditions.
A Ni–Al bimetallic catalyzed enantioselective C–H exo-selective cyclization of imidazoles with alkenes has been developed. A series of bi- or polycyclic imidazoles with β-stereocenter were obtained ...in up to 98% yield and >99% ee. The bifunctional SPO ligand-promoted bimetallic catalysis proved to be critical to this challenging stereocontrol.
•A discrete element model was developed to investigate soil flow dynamics.•Kinetic energy was the most prominent, followed by body energy and contact energy.•The simulated heap angle decreased ...exponentially during the course of simulation.•Particle size affected the kinetic energy of the particle assembly.•Particle size had negligible effects on the simulated angle of repose.
Understanding soil flow properties is important for designing high-performance soil-engaging tools in agriculture. In this study, soil flow tests were conducted for a sandy loam soil using the lifting cylinder method to obtain the angle of repose (AOR) of the soil. The soil flow was simulated using a numerical model developed based on the discrete element method (DEM). The model was validated with the measured AOR. The validated model was then used to monitor dynamic properties of soil flow. Results of simulated kinetic energy showed that particles were most dynamic at the beginning of the flow process. The boundary work accumulated linearly over time, maximizing when all particles flowed out of the cylinder. The body and friction energies were also accumulating, but with varying accumulation rates over time. The simulated heap angle decreased exponentially over time during the flowing process, and the simulated AOR (29.0°) was obtained when the heap became stable. This simulated AOR matched the measured AOR with a relative error of 1.7%. Model particle diameter significantly affected the kinetic energy of particles but had little effect on the simulated AOR. The model developed in this study was capable of capturing dynamics of particle assembly and individual particles.
The dominant paradigm of “one gene, one target, one disease” has influenced many aspects of drug discovery strategy. However, in recent years, it has been appreciated that many effective drugs act on ...multiple targets rather than a single one. As an integrated multidisciplinary concept, network pharmacology, which is based on system biology and polypharmacology, affords a novel network mode of “multiple targets, multiple effects, complex diseases” and replaces the “magic bullets” by “magic shotguns.” Chinese herbal medicine (CHM) has been recognized as one of the most important strategies in complementary and alternative medicine. Though CHM has been practiced for a very long time, its effectiveness and beneficial contribution to public health has not been fully recognized. Also, the knowledge on the mechanisms of CHM formulas is scarce. In the present review, the concept and significance of network pharmacology is briefly introduced. The application and potential role of network pharmacology in the CHM fields is also discussed, such as data collection, target prediction, network visualization, multicomponent interaction, and network toxicology. Furthermore, the developing tendency of network pharmacology is also summarized, and its role in CHM research is discussed.
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