Search

Fluorination is a useful approach for tailoring the physicochemical properties of nanocarbon materials. However, owing to the violent reactivity of fluorination, achieving edge-perfluorination of nanographene while maintaining its original π-conjugated structure is challenging. Instead of using traditional fluorination, here, we employed a bottom-up strategy involving fluorine preinstallation and synthesized decafluorinated and perfluorinated warped nanographenes (DFWNGand PFWNG, respectively) through a 10-fold Suzuki–Miyaura coupling followed by a harsh Scholl reaction, whereby precisely edge-perfluorinated nanographene with an intact π-conjugated structure was achieved for the first time. X-ray crystallography confirmed the intact π-conjugated structure and more twisted saddle-shaped geometry of PFWNGcompared to that of DFWNG. Dynamic study revealed that the 26-ring carbon framework of PFWNGis less flexible than that of DFWNGand the pristine WNG, enabling chirality resolution of PFWNGand facilitating the achievement of CD spectra at −10 °C. The edge-perfluorination of PFWNGresulted in improved solubility, lower lowest unoccupied molecular orbital, and a surface electrostatic potentials/dipole moment direction opposite those of the pristine WNG. Likely owing to its intact π-conjugated structure, PFWNGexhibits comparable electron mobility with well-known PC61BM. Furthermore, perfluorination improves thermal stability and hydrophobicity, making PFWNGsuitable for use as a thermostable/hydrophobic n-type semiconductor material. In the future, this fluorination strategy can be used to synthesize other perfluorinated nanocarbon materials, such as perfluorinated graphene nanoribbons and porous nanocarbon.

To address the challenge of nonphase matching in many infrared (IR) nonlinear optical (NLO) materials, despite having substantial NLO coefficients, we present a new strategy for realizing phase matching (PM) in IR NLO materials by manipulating the fractal dimension (FD) of covalent motifs. As a representative demonstration, we select a salt-inclusion chalcogenide system and validate its efficacy. Consequently, we successfully synthesized two new chalcogenides, denoted as K2[K4Cl][Ga5Sn7S24] (1) and [Na4I][Ga9S15] (2). The latter exhibits PM, while the former does not, primarily attributed to their markedly different FD values of the electron localization function map, resulting in distinct optical anisotropy. Compounds 1and 2demonstrate enhanced IR NLO efficiency, measuring 0.25 and 0.70 times that of AgGaS2at 1910 nm, respectively. Notably, compound 2features a wide band gap of 3.10 eV and a substantial-high laser-induced damage threshold (LIDT) of 93.15 MW cm–2@1064 nm (9.6 × AgGaS2). This work illuminates the exploration of new PM IR NLO materials derived from nonphase matching counterparts.

Rare-earth infrared nonlinear optical (IR NLO) compounds have garnered significant attention due to their abundant electronic structures. However, their NLO efficiency has been relatively modest, attributed to the localization of valence electron shells in rare-earth metals. Traditional design strategies for IR NLO materials have predominantly focused on MQ4(M= metal, Q= S or Se) tetrahedra, with limited exploration of MQ6octahedra. We introduce a novel approach to enhance NLO effects by incorporating distorted mixed anionic octahedral M(S/X)6groups. To illustrate this strategy, we undertake structure modification and optimization of IR NLO performance using the Y–Ga–Ge–S system as an example. The synthesis of a new rare-earth chalcogenide, Y6Ga2GeS14(1), serves as a foundation. Further halogen atom substitution yields Y6Ga4.2S13.6Cl3.4(2), Y6Ga2.83Ge2S16.75Cl (3), and Y6Ga2.83Ge2S16.5Br1.5(4). All compounds demonstrate remarkable NLO performance, including moderate NLO coefficients (0.17–0.70 × AgGaS2), large laser-induced damage thresholds (LIDTs) (3.78–6.19 × AgGaS2), and a broader transmission range (0.5–14.9 μm). The incremental enhancement of NLO efficiency in compounds 1–4can be attributed to symmetry breaking induced by halogen atom substitution and increased distortion of the octahedral M(S/X)6motifs in their structures, validating the effectiveness of our strategy. Notably, this strategy concurrently increases the band gap and LIDT, overcoming the NLO–LIDT incompatibility, being strikingly different from other reported approaches. This work provides new insights into optimizing the NLO performance of rare-earth IR NLO compounds through the modulation of octahedral motifs.

Non-centrosymmetric (NCS) structure is an indispensable prerequisite for second-order nonlinear optical (NLO) material. Currently, the mainstream approach for designing new NCS structures still relies on chemical substitution, necessitating an urgent infusion of fresh ideas. In this work, two isomorphic sulfides AeMn6Ga6S16(Ae = Ca, 1; Sr, 2) are afforded by modifying the skeleton of centrosymmetric (CS) Mn2Ga2S5viaintroducing strong electropositive alkaline-earth cations. Concretely, the incorporation of Ca2+/Sr2+cations allows the elementary [MnGaS9]∞chains to reconfigure into bumpy [MnS6]-[GaS4] layers in a new engagement manner, thus enabling the conversion from CS to NCS structure. Such modifications cause not only strong second-harmonic generation (SHG) responses (∼1.5 × benchmark AgGaS2@1,700 nm), but also significantly feasible bandgaps (2.60–2.64 eV) compared to the sulfide Mn2Ga2S5(1.36 eV), which ultimately facilitate ultrahigh laser-induced damage thresholds (4.4–6.6 × AgGaS2@1,064 nm for compounds 1and 2). The present study offers an ingenious approach for the transformation of CS to NCS structure.

Incorporation of monovalent Ag+or Li+ions into the anionic groups MQ22−(M = Ga, In; Q = S, Se) within diamond-like structures holds great promise for the second-order nonlinear optical (NLO) crystals. However, these crystals are significantly challenged by a low laser-induced damage threshold (LIDT) or the drawbacks associated with silica tube corrosiveness, which severely limit their suitability for high-power applications. In this study, we employed the unusual polycationic substitution strategy based on ZnSe, specifically [Se4Zn13]Se24→ [ClRb3Ba]Se24, to design and synthesize a novel salt-inclusion chalcogenide, denoted as [Rb3BaCl][In8Se14] (1). Compound 1 shares similarity with AgInSe2, as it maintains crystallographic symmetry in the space group I-42dand possesses a compressed chalcopyrite-type selenide structure. Remarkably, compound 1 displays remarkable phase-matching second-harmonic generation (SHG) intensity (2.0 × AgGaS2@2.90 µm) owing to the parallel arrangement of tetrahedral InSe4units. Moreover, the incorporation of the polycation [Rb3BaCl]4+that promotes the enhancement of the band gap (2.02 eV), avoiding two-photon absorption of 2.09-µm laser, combined with a low thermal expansion coefficient, enables compound 1 to exhibit a substantial LIDT (3.2 × AgGaS2@2.09 µm). This study establishes the potential of polycationic substitution within diamond-like structures for the rational design of exceptional mid- and far-infrared NLO materials.

Strong second-harmonic generation (SHG) and phase-matchable capability at specific transmittance windows are crucial to the real application of nonlinear optical crystals. Herein, an efficient strategy of introducing Pb2+with stereochemically active lone-pair electrons into non-phase-match-able Ga2Se3viaenhancing the anisotropy microstructure is first applied to meet phase-matchable SHG intensity requirements, offering a selenide, namely, PbGa4Se7, which is designed and synthesized with a diamond-like anionic framework, where Pb2+cations reside in a parallel arrangement. As expected, PbGa4Se7possesses a large SHG coefficient of 3.3 times that of AgGaS2under the incident laser of 1910 nm. Moreover, PbGa4Se7displays a high laser-induced damage threshold of 7.0 times that of AgGaS2at 2090 nm, which originates from the low anisotropy of thermal expansion coefficient (0.36) and suitable optical band gap (2.1 eV). Theoretical calculations demonstrate that the considerable phase-matchable SHG response of PbGa4Se7can be attributed to the synergies of tetrahedral GaSe4and pyramid PbSe3microstructural blocks with additional anisotropy and polarizability.

The template-based design of the crystal structure is a direct and highly efficient method to achieve optimal nonlinear optical (NLO, meaning second-order NLO) performances. The structural flexibility of porous salt-inclusion chalcogenides (SICs) provides an alternative platform for modulating the enlargement of the band gap (that is generally positive with laser-induced damage threshold) and second harmonic generation (SHG) response simultaneously. By applying the “pore reconstruction” strategy to SIC [K3Cl][Mn2Ga6S12] (1), a new derivative K3Rb3[K3Cl][Li2Mn4Ga12S27] (2) is successfully isolated, which unusually features a heterologous nanopore framework with inner diameters of 8.90 and 9.16 Å. Guided by such a strategy, compound 2possesses the widest band gap (3.31 eV) among the magnetic NLO chalcogenides; this finding is dominantly attributed to the porous structure and the “dimensional deduction” effect. Moreover, phase 2displays a remarkable phase-matchable SHG intensity (1.1 × AgGaS2at the incident laser of 1910 nm) that originated from the oriented alignment of NLO-functional motifs, as well as the rich terminal S atoms in the nanopore structure. Furthermore, the “pore reconstruction” strategy offers an efficient pathway to explore potential NLO candidates with excellent comprehensive performances; in particular, it settles the conflicting issue of enhancing the band gap (>3.0 eV) and SHG intensity (>1.0 × AgGaS2) concurrently.

Purpose: We present a case of retinal vasculopathy with cerebral leukodystrophy and review the usefulness of optical coherence tomography angiography (OCT-A) in the assessment of long-term outcomes.Case description: A 31-year-old woman developed sudden-onset scotoma in her right eye. Fundus examination and fluorescein angiography showed a patch of soft exudate and capillary nonperfusion in the posterior pole and outside the vascular arcades. OCT-A revealed that the initial vessel density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) of the right eye were 32% and 49.2%, respectively. Interestingly, over time, the VD of the SCP and DCP gradually decreased to 23.1% and 26.2%, respectively. In contrast, the initial VD of the SCP and DCP of the left eye were both stable at 44.3% and 56.2%, respectively, and only decreased slightly to 39.3% and 45.7%, respectively, over time. The average VD loss of the SCP and DCP, assessed over 1 year, was 8% and 13%, respectively, in the right eye, and 3% and 6%, respectively, in the left eye.Conclusion: Based on this case report, in which we demonstrated a long-term decline in VD of the macula in a young woman with mild retinal vasculopathy with cerebral leukodystrophy, we suggest that there is a potential and valuable role for OCT-A in this rare disease.

Hundreds of C60derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lacks of guidelines to update C60-based ETMs with excellent photoelectric properties. In this work, crystallographic data of eight C60-based ETMs, including pristine C60and the well-known PCBM as well as six newly synthesized fullerenes, are analyzed to establish the connections between derivatized structures and photoelectric properties for the typical carbon cluster of C60. In terms of packing centroid-centroid distance between neighboring carbon cages, the crystallographic data are useful for probing photoelectric properties, such as electrochemical properties, electron mobility and photovoltaic performances, and therefore facilitate to design novel C60-based ETMs for PSCs with high performances.

Magnetic infrared (IR) nonlinear optical (NLO) materials, particularly those containing d-block metals, have attracted considerable attention due to the contributions of d-orbitals to large NLO efficiency. However, the d–d transitions from the d-block metals lead to strong optical absorption and narrow band gap, seriously hindering their practical applications. The structural flexibility of salt-inclusion systems provides a good opportunity for modulating the crystal field of magnetic ions to suppress the d–d transitions but allowing the NLO-active d–s and d–p transitions. These ideas afford a new salt-inclusion sulfide [K3Cl][Mn2Ga6S12], which features a rare nanoporous [MnGa3S6]−framework with tunnels of inner diameter of 9.0 Å and possesses a broad transparency (0.39–25.0 μm) and the widest band gap (3.17 eV) among all magnetic IR NLO chalcogenides. Remarkably, it exhibits a strong phase-matchable second-harmonic generation intensity (0.8 × AgGaS2at 1910 nm and 3.1 × AgGaS2at 1064 nm) and a high laser-induced damage threshold (12.5 × AgGaS2at 1064 nm), achieving the important criteria of an advanced IR NLO material.

Commercially available infrared (IR) nonlinear optical (NLO) materials, such as diamond-like AgGaQ2(Q = S, Se), display large NLO coefficients but relatively low laser-induced damage thresholds (LIDTs), which seriously hinder their widespread laser applications. Herein, the “one-for-multiple substitution” strategy, namely, [SZn46++ 5Zn2+⇒ A++ 5Ga3+] (A = K, Rb and Cs), is applied on the diamond-like zinc-blende ZnS, and affords three new polar ternary crystals AGa5S8(A = K, Rb and Cs) through the solid-state method. These compounds inherit the diamond-like anionic backbone framework in ZnS where the NLO functional motifs GaS4are arranged in a parallel manner. This characteristic accounts for the remarkable phase-matchable second-harmonic generation intensities (1.1–1.2 × AgGaS2). In addition, the inclusion of the highly electropositive A+cations affords a band gap ranging from 3.10 to 3.37 eV, which facilitates the improvement of LIDT (9.3–12.4 × AgGaS2). To the best our knowledge, crystals AGa5S8(A = K, Rb and Cs) are the first series of ternary A-inclusion chalcogenides with large second-harmonic generation responses (≥1.0 × AgGaS2) and wide band gaps (≥3.0 eV), fulfilling the rigorous requirements of outstanding IR NLO materials. In addition, the “one-for-multiple substitution” strategy presents the great significance of diamondlike structure evolution and provides a remarkable opportunity to achieve NLO materials.

The nonlinear optical (NLO) efficiency (dij) and laser-induced damage threshold (LIDT) of a material are mainly determined by their covalency and ionicity, respectively, the incompatibility between which makes balancing the dijand LIDT challenging in an IR NLO material. The topological feature (fractal dimension) of the electron localization function (ELF) map (distribution of covalency and ionicity) was evaluated for a series of NLO materials, and, phenomenologically, the fine mixing of covalency and ionicity will benefit a balanced dijand LIDT. Chemical bonds with different interaction strengths were introduced simultaneously to mix the covalency and iconicity finely, and three new IR NLO sulfides, A2Ba3Li6Ga28S49(A = K, 1; Rb, 2; Cs, 3), were obtained. They exhibit a strong NLO efficiency (1.9–2.1 × AgGaS2at 1064 nm and 0.5–0.6 × AgGaS2at 1910 nm) and high LIDTs (16.7–18.0 × AgGaS2), which fulfill the criteria of being promising IR NLO candidates. This study provides a new method for designing high-performance IR NLO materials based on the topological features of the ELF.

Exploration of a new nonlinear optical (NLO)-active functional motif is important in the rational design of promising infrared (IR) NLO materials. Compared with typical tetrahedral MQ4(M = IIB, III, IV metals; Q = S, Se) motifs, MQ3(M = As, Sb) pyramids favor high second-harmonic generation (SHG) efficiency while frequently hindering phase matching (PM) because of excessively large optical anisotropy. The surfactant–thermal method was first adopted to achieve PM in MQ3-containing systems and synthesize mixed covalent–ionic IR NLO materials. Two new thioarsenates of AMnAs3S6(A = Cs, Rb) exhibiting strong PM SHG efficiencies comparable to commercial AGS and laser-induced damage thresholds of one order higher than AGS were obtained. The [As3S6]3–unit in their structures is an unprecedented NLO-active functional motif, which can be useful in designing new IR NLO compounds with large SHG efficiency. In addition, the surfactant–thermal method provides a new general strategy for synthesizing new IR NLO materials.

Noncentrosymmetry (NCS) is a prerequisite for second-order nonlinear optical (NLO) materials. In this work, a new polycation-substitution-induced centrosymmetry (CS)-to-NCS transformation strategy was applied in CS RbGaS2, affording two novel NCS salt-inclusion chalcogenides: [ABa2Cl][Ga4S8] (A = Rb, 1; Cs, 2). Remarkably, they exhibit the key merits of both Vis and IR NLO candidates, including strong phase-matchable second harmonic generation intensities (10.4–15.3 × KH2PO4at 1064 nm; 0.9–1.0 × AgGaS2at 1910 nm), high laser-induced damage thresholds (11–12 × AgGaS2), and a wide transparent window. Their prominent NLO performances originate from the orderly packing of T2-supertetrahedral Ga4S10motifs resulting from the template effect of acentric polycation [ClA2Ba3]7+. The CS-to-NCS transformation first realized by polycation-substitution-induced NLO-functional motif ordering provides an effective approach for designing new NLO materials.

Enhancement of the nonlinear optical (NLO) output power of lasers requires urgent development of an NLO crystal with a significant second-harmonic generation (SHG) response and sufficient birefringence for phase-matching capability; however, simultaneously optimizing these two key parameters remains a great challenge. In contrast to traditional single-anion units, the stereochemically-active lone pair Sb3+ion is coordinated by S2−and I−ions to yield the mixed-anionic SbSI chalcohalide that can enhance hyperpolarizability and anisotropic polarizability concurrently. As anticipated, SbSI exhibited the largest SHG response (5.7 × AgGaS2@1.91μm) among phase-matching Sb-based sulfides, the favorable laser-induced damage threshold (LIDT, 2.3 × AgGaS2@2.09μm), and the giant calculated birefringence (0.62@1.91 μm). Structural analysis and computational simulations indicate that the highly polarizable mixed anion determine the enormous SHG response and birefringence.

The diamond-like structure is characterized by the well-arranged parallel tetrahedral units, which hold significant importance for infrared nonlinear optical (NLO) applications. By employing an unconventional substitution strategy, a diamond-like ZnS (sphalerite) template was utilized to replace the several ZnxSytetrahedra with one-dimensional [Na2PbI] infinite chains, resulting in the successful design and synthesis of a salt-inclusion sulfide, [Na2PbI][Ga7S12] (1). Remarkably, the highly parallel-oriented [Ga7S16] double T2-supertetrahedron units and the presence of Pb2+-centered polyhedra contribute to its exceptional second-harmonic generation (SHG) intensity (2.6 × AgGaS2@1800 nm), belonging to the top-performing in salt-inclusion chalcogenides. Furthermore, compound 1possesses an appropriate band gap (Eg= 2.53 eV) and exceeds the two-photon absorption of 1064 nm, mainly resulting in a high laser-induced damage threshold (LIDT, 3.6 × AgGaS2). Particularly, phase 1achieves a phase-matching ability (birefringence: 0.069) that template α-ZnS cannot possess. These characteristics indicate that this unconventional substitution strategy provides insights into the design of excellent diamond-like NLO compounds.

C30H22S2, triclinic, P1̄ (no. 2), a= 7.604(4) Å, b= 11.556(5) Å, c= 13.090(7) Å, α= 93.964(8)°, β= 93.209(8)°, γ= 90.619(9)°, V= 1145.7(10) Å3, Z= 2, Rgt(F) = 0.0497, wRref(F2) = 0.1295, T= 296(2) K.

Two new infrared (IR) nonlinear optical (NLO) sulfides, Na2Ga2GeS6and Na2Ga2SnS6, were obtained by mixing different typical NLO-active motifs GaS4and GeS4/SnS4in the alkali metal-containing system. The IR NLO sulfides present laser-induced damage thresholds that are 18.1 and 17.9 times that of the reference AgGaS2(AGS) and second-harmonic generation efficiencies that are 0.8 and 1.1 times that of AGS. These properties originate from the GaS4, GeS4, and SnS4tetrahedral blocks in the structures of the sulfides. Both compounds also exhibit a broad transparency range and type-I phase-matching behavior, which support their high potential in high-power laser applications. This work sheds new light on the development of promising mid-IR NLO materials by combining different NLO-active motifs.

ABSTRACTSafe operation of nuclear power plant is one of the most important tasks in nuclear power development. This justifies the variety of methods that have been proposed to support the operators in the task of plant condition monitoring, fault detection, and diagnosis. A number of hybrid fault detection and diagnosis methods have also been proposed, with their attendant weaknesses. This work proposes the hybrid of principal component analysis (PCA), signed directed graph (SDG), and Elman Neural Network (ENN) for fault detection, fault isolation, and severity estimation, respectively. The proposed hybrid method is verified with the data derived from Personal Computer Transient Analyzer (PCTRAN) simulation. The verification result shows that the PCA-based fault detection methodology realized timely detection of anomaly in the simulated nuclear power plants system, the SDG-based fault recognition method was able to isolate the system abnormality and identify the root causes, and the ENN-based fault severity estimation method presents the failure fraction of fault, representing the severity. With this integrated hybrid method, more fault information is provided for the operators, which serves as a good foundation for further decision-making and interventions.

Investigation of the alkaloids from Peganum harmalaseeds yielded two pairs of unique racemic pyrroloindole alkaloids, (±)-peganines A–B (1–2); two rare thiazole derivatives, peganumals A–B (3–4); six new β-carboline alkaloids, pegaharmines F–K (5–10); and 12 known analogues. Their structures, including stereochemistry, were elucidated through spectroscopic analyses, quantum chemistry calculations, and single-crystal X-ray diffraction. Notably, the incorporation of pyrrole and indole moieties in peganines A–B, thiazole fragments in peganumals A–B, and a C-1 α,β-unsaturated ester motif in pegaharmine F (5) are all rare, and their presence in the genus Peganumwere demonstrated for the first time. All isolates were tested for antiproliferative activities against the HL-60, PC-3, and SGC-7901 cancer cell lines, and compounds 9, 11, 12, and 13exhibited moderate cytotoxicity against HL-60 cancer cell lines with IC50values in the range of 4.36–9.25 μM.

Quaternary metal thiophosphates containing second-order Jahn–Teller distorted d10Ag+and lone-pair cations, Ag3Bi(PS4)2(1), Ag7Sn(PS4)3(2), and Ag7Pb(PS4)3(3), were obtained by solid-state synthesis. The structural frameworks of 2and 3feature an infinite 1-D interchiral double helix ∞1(Ag3P2S11), which is rare in inorganic compounds. Compound 3undergoes a significant first-order structural phase transition from monoclinic to hexagonal at ∼204 °C. This can be ascribed to the significant mismatch in the expansion coefficients between Pb–S (Ag–S) and P–S bonds evaluated by bond valence theory. The three compounds are Ag+ionic conductors, and Ag+ion migration pathways are proposed by calculating maps of low bond valence mismatch. Moreover, the optical properties of the three compounds were studied, and electronic structure calculations were performed. The combination of second-order Jahn–Teller distorted d10cation and lone-pair cation provides a new strategy to explore new metal thiophosphates with interesting structures and promising properties.

Two new phases in the Ag–Cd–P–S system containing two second-order Jahn–Teller (SOJT) distorted d10cations (Cd2+and Ag+), namely, Ag2Cd(P2S6) (1) and AgCd3(PS4)S2(2), are obtained via medium-temperature solid-state synthesis. Compound 1exhibits a two-dimensional layered structure and undergoes a first-order structural phase transition at approximately 280 °C. This outcome can be ascribed to the significant mismatch in the expansion coefficients between Cd–S (Ag–S) and P–P (P–S) bonds evaluated through bond valence theory. The three-dimensional non-centrosymmetric (NCS) framework of 2is constructed by two types of tetrahedral layers consisting of corner-shared CdS4, AgS4, and PS4tetrahedra. Compound 2exhibits second harmonic generation (SHG) intensity of 0.45 times that of commercial AgGaS2(AGS) at a laser irradiation of 1.85 μm and an optical band gap of 2.56 eV, and no intrinsic vibrational absorption of chemical bonds is observed in the range of 2.5–18.2 μm. Both phase transition in 1and SHG properties in 2are closely related to the SOJT distorted d10cations and diverse phosphorus–sulfur polyanions (PaSb)n−, which together can easily result in NCS distorted structures and interesting properties.

Noncentrosymmetric phosphides have garnered significant attention as promising systems of infrared (IR) nonlinear optical (NLO) materials. Herein, a new quaternary diamond-like phosphide family I–III–IV2–V4and its inaugural member, namely, CuInSi2P4(CISP), were successfully fabricated by isovalent and aliovalent substitution based on ZnGeP2. First-principles calculations revealed that CISP has a large NLO coefficient (d14= 110.8 pm/V), which can be attributed to the well-aligned tetrahedral [CuP4], [InP4], and [SiP4] units. Remarkably, the extremely small thermal expansion anisotropy (0.09) of CISP enables it to exhibit a considerable laser-induced damage threshold (LIDT, 5.0 × AgGaS2@1.06 μm) despite the relatively narrow band gap (0.81 eV). This work improves the chemical diversity of inorganic phosphide and promotes the development of phosphide systems, which may provide valuable perspectives for future exploration of IR NLO materials.

Nonlinear optical (NLO) materials are of great importance in converting the frequency to extend the laser spectrum in mid- and far-infrared (IR) regions where lasers operate poorly or are unavailable. However, the contradiction between large second-harmonic generation (SHG) intensity and wide band gap (Eg) is a long-standing problem for IR NLO materials. To address the issue, metal chalcogenides have been successfully synthesized and developed excellent optical properties in the past few decades. As a newly discovered category of chalcogenides, salt-inclusion chalcogenides with distinctive structures and brilliant performances have been placed great expectations to be a novel problem-solving. In this review, 52 compounds in this thriving family are categorized via dimensions of host and guest parts, further discussing the relationships between their structures and NLO properties, as well as future perspectives of this family.

Counsellors’ journal is an important record for everyday’s counsellors’ work situation, it plays an important role in the daily students management work, design of counsellors’ journal management system in CRP digital campus information platform (CRP) is divided into three parts: electronic form content design, the management function design and interconnection & interworking work flow design between counsellors' journal management system and other systems. Students work data collected by the counsellors' journal management system has important guiding significance to the students monitoring and management, student management work could be promoted from the analysis and use of collected data of counsellors’ journal.

Based on the analysis of the current main problems in vehicle usage examination and approval management, we use J.Office collaborative developing platform to do form design, process design and form-process-personnel binding to design and implement network vehicle usage examination and approval process in CRP digital campus information management platform (CRP) to solve these problems.

Teachers’ journal is an important records of teaching situation of each lesson, it is also an important part of the daily teaching, design of teachers’ journal management system in CRP digital campus information platform (CRP) is divided into three parts: form design of teachers’ journal, the management function design of teachers' journal management system and interconnection and interworking work flow design between teachers' journal management system and other systems. Teachers’ teaching data collected by the teachers’ journal management system has important guiding significance to the teaching monitoring and operation, teaching management could be better from the analysis and use of collection data of teachers’ journal.

This paper gives a teaching resources platform that is a comprehensive feature rich, convenient use, strong interactivity based on cloud computing technology. Platform includes various cloud functions and cloud spaces such as identity authentication function, single sign-on function, resources upload/download function, resources collection function, resource integration function, instant communication function, teacher resource cloud space, student resources cloud space, theme resources cloud space, department resources cloud space and schools resources cloud space. Compared with available technology, we can build an no capacity constraints cloud platform for storage and sharing of teaching resources based on the cloud computing technology, this teaching resources cloud platform is an open, interactive public service platform of educational resources.

Paper seal examination and approval process is low efficiency and high cost, with the development of science and technology, the use of network especially Internet has become a trend for seal examination and approval process. We’ll use J.Office collaborative developing platform to do form design, process design and form-process-personnel binding to design and implement network seal examination and approval process.

In image processing, removal of noise without blurring the image edges is a difficult problem. Aiming at orthogonal wavelet transform and traditional threshold’s shortage, a new wavelet packet transform adaptive threshold image de-noising method which is based on edge detection is proposed. By edge detection method, the wavelet packet coefficients corresponding to edge which is detected and other non-edge wavelet packet coefficients are treated by different threshold. Using the relativity among wavelet packet coefficients and neighbor dependency relation, at the same time, adopting the new variance neighbor estimate method and then the adaptive threshold is produced. From the experiment result, we see that compared with traditional methods, this method can not only effectively eliminate noise, but can also well keep original image’s information and the quality after image de-noising is very well.

Design of digital teaching platform of the Internet of Things (IOT) is to solve the technical problem about how to provide all-digital, high-simulation and feature-rich digital teaching platform of IOT. This design includes the operating terminal, the master node of IOT, slave node of IOT, RFID Read/Write modules and RFID labels. Compared with the existing technology, this design can simulate the operation and usage of IOT in various application environments, it is very convenient for students to study and master the basic technology of IOT, it can be widely used in all kinds of school teaching and scientific research.

Aim at leave examination and approval requirements of digitization and networking, we use J.Office cooperative office platform as developing platform of design and implementation of network leave examination and approval system of CRP digital campus network information platform (CRP), we use leave examination and approval process of Hainan Vocational College of Political Science and Law as an example to give specific implementation steps and demo about network leave examination and approval system.

As a high-frequency, broadband wireless transmission system, wireless microwave transmission system is still paid attention by the whole world. The construction and function of wireless microwave transmission system is introduced in this paper. This paper focuses on the design of outdoor unit for wireless microwave transmission system.

The high frequency and ultrasmall mass of graphene make it an ideal material for ultrasensitive mass sensing. In this article, based on the all-optical technique, we propose a scheme of an optical mass sensor to weigh the mass of a single atom or molecule via a doubly clamped Z-shaped graphene nanoribbon (GNR). We use the detection of shifts in the resonance frequency of the Z-shaped GNR to determine the mass of an external particle landing on the GNR. The highly sensitive mass sensor proposed here can weigh particles down to the yoctogram and may eventually be enable to realize the mass measurement of nucleons.

One classic algorithm usedin template matching is normalized cross correlation method. It often achieveshigh precision. But it does not meet speed requirements for time-criticalapplications. To solve that issue, a speed-up way of template matching isproposed. The fast matching way bases on pyramid hierarchical searchingalgorithm. It adopts two template matching methods to match images, which baseon rough matching proceeds local matching precision. Firstly, the coarsematching is performed based on gray-scale projection algorithm. Secondly, theprecise matching is made based on several small block matching. The new way iscompared to conventional approach without pyramid hierarchical searching byexperiments. Experimental result demonstrates that the proposed way efficientlyimproves the speed of template matching and the precision is unchanged.

In order to improve accuracy of constant altitude fly at low altitude and fly track of glide down to fixed altitude, aeroplane’s control scheme of glide down to fixed low altitude with PID compensatory link were designed. At the same time, the corresponding control laws had been designed. After simple analysis about working principle of the aeroplane’s control system, simulation researches were done to optimize designed control laws, so that achieving expectant requirement. Simulation results show that designed control scheme and control law were accurate and effective.

According to the main features of many switch signals, very strict logical waves, complex electromagnet interference in the weaving machinery, the embedded design scheme based on SoC technique is employed. The consideration of designing a universal electrical control system for weaving machinery based on SoC and FPGA is presented by making full use of the internal structure and the resource configuration. In accordance with the characteristics of weaving machinery, the proposed design methods are applied in the control system of glove knitting machinery. The typical structure and the partial electromagnet waveforms are provided. The practical application shows that the peripherally hardware circuits and the control programs are simplified in the embedded control system based on SoC technique. The reliability of the whole equipment is rapidly improved. This system can be widely applied in weaving machineries.

Exploring new infrared nonlinear optical (IR NLO) materials with superior overall properties is scientifically and technically important. However, large second-order harmonic generation (SHG) efficiencies and high laser-induced damage thresholds (LIDT) are incompatible, which makes realizing this goal a challenge. The IR NLO performance of an A-NIIB-MIIIA-Q (Q: chalcogen) system was optimized by simultaneously modulating A/(M + N) and M/N ratios (A: alkali metal; N, M: tetra-coordinated metals), and SHG–LIDT balance was achieved. Three new sulfides, KCd3Ga5S11(1), RbCd4Ga3S9(2), and Cs2Cd2Ga8S15(3), containing the same CdS4and GaS4but with different A/(Ga + Cd) and Ga/Cd ratios were obtained. Among these compounds, compound 3exhibits both the largest SHG efficiency (0.5 × AgGaS2) and LIDT (35 × AgGaS2), which can be ascribed to the Ga/Cd modulation for enhancing the NLO functional motif distortions and SHG efficiency as well as the A/(Ga + Cd) modulation for enlarging the band gap and LIDT. Remarkably, compound 3is the first phase-matchable IR NLO material in the A-NIIB-MIIIA-Q family. This article proposes a novel avenue to explore infrared nonlinear materials with superior comprehensive properties by modulating the A/(M + N) and M/N ratios.

Herein, a nitrogen-embedded quintuple [7]helicene (N-Q7H) with an azapentabenzocorannulene core, which can be considered to be a helicene/azacorannulene hybrid π-system, was synthesized from azapentabenzocorannulene in a three-step process. N-Q7His the first example of a multiple helicene with an azabuckybowl core. Single-crystal X-ray diffractometry unambiguously confirmed the structure of the propeller-shaped hybrid π-system. Owing to nitrogen-atom doping in the multiple helicenes and effective hybridization between the helicene and azacorannulene, N-Q7Hexhibits considerably redshifted absorption and emission (yellow-to-green color change and green-to-near-infrared fluorescence change) relative to the azapentabenzocorannulene core. The broad absorption from the ultraviolet–visible to the NIR region is ascribable to the allowed transition between the highest occupied molecular orbital and the lowest unoccupied molecular orbital after symmetry breaking, as revealed by density functional theory calculations. Compared to previous propeller-shaped multiple helicenes with corannulene or hexabenzocoronene (etc.) as cores, N-Q7Hdemonstrates a significantly higher NIR fluorescence quantum efficiency of 28%. Additionally, the chiral-resolution and redox properties of N-Q7Hwere investigated. The excellent photophysical and inherent chiral properties of N-Q7Hsuggest that azapentabenzocorannulene can be used as an outstanding nitrogen-embedded core to construct novel multiple helicenes with wide application potential, including as NIR fluorescent bio-probes.

Semiconductor conductivities depend largely on the crystal structures and the associated electronic structures. If the electronic structures can be switched reversibly in the same crystal structure, then a drastic conductivity change may be controllable. The effect of electron transfer (ET) on semiconductor conductivity remained elusive so far. In this work, a series of two pillared inorganicorganic hybrid photochromic semiconductors (PSCs), [(CQ)Pb3X6(H2O)]·2H2O [X = Cl (1) and Br (2), CQ = N-4,4′-bipyridiniopropionate (viologen)], with II-stacking viologen π-aggregates, are constructed by a bottom-up self-assembly strategy through inorganic skeleton-directed intercalation and intermolecular noncovalent interaction. The conductivities are abnormally “invariant” after photoinduced ET, breaking the convention that the generation of radicals favors conductivity. The abnormally “invariant” conductivities are mainly derived from approximate electronic couplings before and after ET between II-stacking viologen π-aggregates.

The convergence of voice and data on the multiservice core allows virtually anyone to create communications services and offer them through a Web page over public networks. Session initiation protocol (SIP) phone users may launch new services in SIP messages. The traditional domain of service creation by the service provider for voice traffic networks is opening up to third parties. This creates a host of challenges for service creation tool sets to support this new paradigm of service authoring. This paper presents these challenges and remedies as addressed by a third‐party programmable, service‐mediation‐enabled feature server. It provides a third‐party programmable service authoring and service logic execution environment, which supports the deployment of innovative multiservice features while resolving feature interactions and integration into existing operations, administration, maintenance, and provisioning (OAM&P) elements. It leverages the Java* Telephony API (JTAPI)‐based Lucent Technologies Full Circle™ application programming interfaces (APIs), Java APIs for Integrated Networks (JAIN*)/Parlay, SIP, and Extensible Markup Language (XML) to maximize flexibility in integrating new services across multiple servers in the packet network.

The telecommunications industry today is facing an increasing degree of complexity due to the proliferation of available technologies and separate implementations of voice and data networks and services. Recent trends in the industry toward a convergence of telephony/computer technologies, networks, and services create an opportunity for reducing complexity in the converged voice/data network. The converged telecommunications network will be packet based, providing integrated voice/data/video services with third‐party programmability to any subscriber, anywhere, over any access media. This paper describes an architectural approach to meet these challenges. A set of guiding principles is formulated and used for developing the converged network and service architectures. These principles, which provide an overall framework for partitioning network and service functions into components, are illustrated using the planned 7R/E™ Packet Solutions system and service architectures to build component‐based converged voice and data services with interfaces to operations, administration, maintenance, and provisioning (OAM&P) frameworks for industry‐grade reliability, availability, and security.

Recent changes in the United States telecommunications industry—both regulatory and market driven—provide an environment for integrating wireless and wireline services and the infrastructure used to provide them. Changes in the industry have created competition in local access, deregulation that allows bundling of services and one‐stop shopping, and multiple personal communication services (PCS) licensees, each with the desire to differentiate its service offering with value‐added capabilities. Integrating wireless and wireline services enables service providers to offer a seamless wireless/wireline service and help control infrastructure and ongoing administrative costs. This paper highlights some advantages for integrating these systems in the U.S. market today. We describe a vision of the long‐term services architecture for a functional solution and several near‐term product concepts designed to provide an integrated wireless/wireline service.

With the rapid development of cloud computing technology and application, the construction of teaching resources platform based on cloud space has become a development trend and direction of the education informatization, this paper presents the existing problems in teaching resources platform and the ideas and methods about how to construct teaching resources platform based on cloud space

Achieving large phase-matchable (PM) nonlinear optical (NLO) efficiency and high laser-induced damage threshold (LIDT) in an infrared second-order NLO (IR NLO) material is the most crucial technical endeavor but the most challenging. A synergetic strategy of modulating NLO functional motifs and vacancy sites for excellent comprehensive performances is proposed. The application of such a strategy in salt-inclusion systems affords two chalcogenides [K4Cl][CdGa9Q16] (Q = S, 1; Se, 2), which possess the important merits of a practical IR NLO material, including large PM NLO efficiency (0.9 and 2.4 × AgGaS2) and high LIDTs (22.6 and 7.7 × AgGaS2). Remarkably, compound 2has the strongest SHG intensity among all known PM salt-inclusion chalcogenides. In addition, the strategy also enhances the structural anisotropy and renders 2the first PM one among all known NLO salt-inclusion selenides. This work provides a novel design approach of the IR NLO material much more superior than other unique modulations.

Second-order nonlinear optical (NLO) switchable materials are eliciting increased interest because of their widespread optical applications. The stringent requirements of NLO efficiency, laser-induced damage threshold (LIDT), switching ratio, and reversibility for good switches make NLO switching materials considerably rare. In this work, three ternary thioantimonate switches, ASb5S8[A = K (1), Rb (2), and Cs (3)], with thermally driven crystal–glass transitions were obtained by flux solid-state reactions. Their structures are constructed using SbSn(n= 3–5) units with multiple coordination modes, which extend to 1-D chains and 2-D layers, and changeable alkali metals. Compounds 1and 2are noncentrosymmetric and present excellent infrared (IR) NLO properties with the largest phase-matchable NLO response (1.7× and 1.1× AgGaS2) among all known NLO switching materials, which primarily originate from Sb3+with a lone electron pair and S atoms and high LIDTs (10.7× and 7.1× AgGaS2). Remarkably, compounds 1and 2also exhibit prominent switching characteristics, including good reversibility, moderate conductivity, and high second-harmonic generation switching ratios (365.6 and 664.5). All these features indicate their potential in practical switching applications. This work sheds lights on designing IR NLO switches by introducing lone electron pair cations with flexible coordination modes into a chalcogenide system.