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Nanoconfinement offers opportunities to tune physical properties of molecular entities by altering their assembled structures. This also applies to acene-based molecules with potentially rich π–π interactions. Unlike most of the previous cases with acene-based guests directly incorporated into hosts, we take a further step by oligomerizing a fluorescent anthryl monomer, 9-vinylanthracene, inside nanochannels of a metal–organic framework, which is a pillared three-dimensional kagome net of [Zn2(bdc)2(dabco)] (bdc2– = 1,4-benzenedicarboxylate; dabco = 1,4-diazabicyclo[2.2.2]octane). The fluorescence emission of the guest can be significantly enhanced after oligomerization, which is likely due to the suppressed nonemissive interaction between the oligomerized molecules in the nanospace and the MOF wall. The case we have demonstrated for fluorescence enhancement via confined oligomerization provides inspiration for the design of luminescent composites and is encouraging for further exploration of molecules in a nanoconfined space.

Surfactant choice is key in starting the phenomena of artificial morphogenesis, the bottom-up growth of geometric particles from cooled emulsion droplets, as well as the bottom-up self-assembly of rechargeable microswimmer robots from similar droplets. The choice of surfactant is crucial for the formation of a plastic phase at the oil-water interface, for the kinetics, and for the onset temperature of these processes. But further details are needed to control these processes for bottom-up manufacturing and understand their molecular mechanisms. Still unknown are the minimum concentration of the surfactant necessary to induce the processes, or competing effects in a mixture of surfactants when only one is capable of inducing shapes. Here we systematically study the effect of surfactant nature and concentration on the shape-inducing behaviour of hexadecane-in-water emulsions with both cationic (CTAB) and non-ionic (Tween, Brij) surfactants over up to five orders of magnitude of concentration. The minimum effective concentration is found approximately equal to the critical micelle concentration (CMC), or the solubility limit below the Krafft point of the surfactant. However, the emulsions show low stability at the vicinity of CMC. In a mixed surfactant experiment (Tween 60 and Tween 20), where only one (Tween 60) can induce shapes we elucidate the role of competition at the interface during mixed surfactant adsorption by varying the composition. We find that a lower bound of ~ 75% surface coverage of the shape-inducing surfactant with C14 or longer chain length is necessary for self-shaping to occur. The resulting technique produces a clear visual readout of otherwise difficult to investigate molecular events and establish basic requirements for minimum concentration and protocols to find % surface coverage to induce oil self-shaping by surfactant mixtures., 11 pages, 6 figures, Supplementary with 3 tables, 7 figures

The two-dimensional (2-D) framework, [Cu(BTDAT)(MeOH)] {BTDAT = bis-[1,2,5]-thiadiazolo-tetracyanoquinodimethane}, possesses remarkable multi-step redox properties, with electrochemical studies revealing six quasi-stable redox states in the solid state. In situ electron paramagnetic resonance and visible-near infrared spectroelectrochemistry elucidated the mechanism for these multi-step redox processes, as well as the optical and electrochromic behavior of the BTDAT ligand and framework. In studying the structural, spectroscopic, and electronic properties of [Cu(BTDAT)(MeOH)], the as-synthesized framework was found to exist in a mixed-valence state with thermally-activated semiconducting behavior. In addition to pressed pellet conductivity measurements, single-crystal conductivity measurements using a pre-patterned polydimethylsiloxane layer on a silicon substrate provide important insights into the anisotropic conduction pathways. As an avenue to further understand the electronic state of [Cu(BTDAT)(MeOH)], computational band structure calculations predicted delocalized electronic transport in the framework. On the balance of probabilities, we propose that [Cu(BTDAT)(MeOH)] is a Mott insulator (i.e., electron correlations cause a metal-insulator transition). This implies that the conductivity is incoherent. However, we are unable to distinguish between activated transport due to Coulombically bound electron-hole pairs and a hopping mechanism. The combined electrochemical, electronic, and optical properties of [Cu(BTDAT)(MeOH)] shine a new light on the experimental and theoretical challenges for electroactive framework materials, which are implicated as the basis of advanced optoelectronic and electrochromic devices.

Lead halide perovskite (LHP) semiconductors show exceptional optoelectronic properties. Barriers for their applications, however, lie in their polymorphism, instability to polar solvents, phase segregation, and susceptibility to the leaching of lead ions. We report a family of scalable composites fabricated through liquid-phase sintering of LHPs and metal-organic framework glasses. The glass acts as a matrix for LHPs, effectively stabilizing nonequilibrium perovskite phases through interfacial interactions. These interactions also passivate LHP surface defects and impart bright, narrow-band photoluminescence with a wide gamut for creating white light-emitting diodes (LEDs). The processable composites show high stability against immersion in water and organic solvents as well as exposure to heat, light, air, and ambient humidity. These properties, together with their lead self-sequestration capability, can enable breakthrough applications for LHPs.

Crystallization of perovskite structure chromites (ACrO3) in aqueous conditions is difficult owing to the amphoteric nature of the Cr3+ in the alkaline-mediated reaction conditions. This is especia...

Pure metal-organic framework (MOF) layers deposited on porous supports are important candidates for molecular sieving membranes, but their performance usually deviates from theoretical estimations. Here, we combine step-wise scanning electron microscopy imaging, time-resolved synchrotron X-ray scattering, terahertz infrared spectroscopy, and density functional theory calculation to investigate the ZIF-8 membrane formation on two types (polydopamine and TiO2) of functionalized porous supports. Though molecular sieving of ZIF-8 membranes for smaller gases (He, H2, and CO2) can be achieved with both types of functionalized supports, we unravel that the strong interaction between MOF and polydopamine can disrupt the formation of "perfect" MOF crystals at the interface, leading to a "contracted" MOF structure with partially uncoordinated imidazolate ligands. This further affects the low-frequency dynamical parameters of the framework and inhibits the effective seeded growth. Eventually, it leads to an unexpected loss of selectivity for the bulkier gases (N2 and CH4) for ZIF-8 on polydopamine-functionalized supports. This work links the dynamical aspects of MOFs with their gas transport behavior and highlights the importance of regulating the interfacial weak forces to preserve the ideal molecular sieving efficiency of MOF membranes, which also provides guidance for defect engineering of MOF film fabrication for sensing and electronic devices beyond membranes.

The incorporation of photoactive donor-acceptor Stenhouse adduct (DASA) moieties into Metal-Organic Frameworks (MOFs) provides a new route to the development of visible light switching materials. Herein, a DUT-5 mixed-linker defect series was exploited to produce a derivative group of DASA-modified materials via postsynthetic modification (PSM). The photoactive MOFs exhibited conversion stimulated by visible wavelengths and were stable following multiple cycles. Thermodynamic and metastable states persisted over an extended time period.

A punctual and energy-saving operation model and some principles to realize energy-saving operation for train are analysed in this paper in order to reduce the energy consumption and obtain the energy-saving speed curve. According to the basic principles of dynamic programming algorithm, the train operation line is discretized. We reduce the space of state variables by using the maximum capacity operation curve and average speed operation curve. And the cost function for energy and time consumption is constructed according to requirements for punctual and energy-saving operation of trains. The simulation results using specific parameters show that the dynamic programming algorithm using reduced state space has high computational efficiency and effectively reduces the energy consumption of train operation.

Dynamic microscale surface topographies are desired in smart optics, controlling surface wettability and preventing marine biofouling. Voltage-controlled reversible responses have demonstrated potential for reliable reproducibility and stability, fast response, and for actuating thin films fixed over large solid surfaces. To obtain reversible deformation with regular geometric patterns, however, electrical methods have had to be coupled with mechanical stretching/bending and other ways to induce anisotropy. There is a great need and potential for on-demand electrical generation of programmable complex responsive surface patterns. Here we demonstrate a responsive polymer coating over an underlying pattern of counter electrodes which can be activated selectively. We present a patternable electrode printing method to achieve localized and structured wrinkling deformation without mechanical pre-force deformation. We discover that below a minimal separation distance, electrodes below the polymer act as a single electrode. We establish parameters that govern the alignment of wrinkles and quantify the regularity and direction of the new patterns between electrodes separated by larger than this distance. We analyze and quantify the regularity of the formed wrinkling patterns by four disorder metrics: box-counting fractal dimension, tortuosity, angle distribution, and branch number. We demonstrate the application of such electrode/wrinkles-on-demand patterning with a working multi-state light reflection–diffusion–grating device.

Good biological properties for titanium implants will shorten the treatment cycle and improve patient comfort, which are also the main goals of dentistry and orthopaedics. At present, the biological properties of titanium implants are mainly enhanced in two aspects: their surface chemistry and surface morphology. In this study, a surface modification strategy combining bioactive trace elements with surface micromorphology modification was used to enhance the biological properties of pure titanium. A new coating incorporating silicon micropore/microsphere topography was prepared on a titanium plate by micro-arc oxidation (MAO) technology. The properties of the coating and its effects on the adhesion and osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) were further analyzed. The experimental results show that a coating doped with amorphous silicon with micropore/microsphere topography was incorporated onto the titanium surface and the surface roughness in the treated groups was obviously higher than that in the Ti group. In vitro, the presence of a silicon-incorporating coating with a micropore/microsphere topography on the titanium surface significantly enhanced the initial adhesion, proliferation and osteogenic differentiation of BMSCs. These results indicate that the silicon-incorporating coating with micropore/microsphere topography has potential applications in dentistry and orthopaedics.

It is highly desirable to red shift the emission of Y3Al5O12:Ce3+ phosphor to obtain a warmer correlated color temperature (CCT) in applications for blue-light pumped white-light emitting diodes (w...

Zinc oxide (ZnO) nanorods (NRs) have been demonstrated as a promising platform for enhanced fluorescence-based sensing. It is, however, desirable to achieve a tuneable fluorescence enhancement with these platforms so that the fluorescence output can be adjusted based on the real need. Here we show that the fluorescence enhancement can be tuned by changing the diameter of the ZnO nanorods, simply controlled by potassium chloride (KCl) concentration during synthesis, using arrays of previously developed aligned NRs (a.k.a. aligned NR forests) and nanoflowers (NFs). Combining the experimental results obtained from ZnO nanostructures with controlled morphology and computer-aided verification, we show that the fluorescence enhancement factor increases when ZnO NRs become thicker. The fluorescence enhancement factor of NF arrays is shown to have a much stronger dependency on the rod diameter than that of aligned NR arrays. We prove that the morphology of nanostructures, which can be controlled, can be an important factor for fluorescence enhancement. Our (i) effort towards understanding the structure–property relationships of ZnO nanostructured arrays and (ii) demonstration on tuneable fluorescence enhancement by nanostructure engineering can provide some guidance towards the rational design of future fluorescence amplification platforms potentially for bio-sensing.

Electrically deformable surfaces based on dielectric elastomers have recently demonstrated controllable microscale roughness, ease of operation, fast response, and possibilities for programmable control. Potential applications include marine anti-biofouling, dynamic pattern generation, and voltage-controlled smart windows. Most of these systems, however, exhibit limited durability due to irreversible dielectric breakdown. Lowering device voltage to avoid this issue is hindered by an inadequate understanding of the electrically-induced wrinkling deformation as a function of the deformable elastic film thickness. Here we report responsive surfaces that overcome these shortcomings: we achieve fault-tolerant behavior based on the ability to self-insulate breakdown faults, and we enhance fundamental understanding of the system by quantifying the critical field necessary to induce wrinkles in films of different thickness and comparing to analytical models. We also observe new capabilities of these responsive surfaces, such as field amplification near local breakdown sites, which enable actuation and wrinkle pattern formation at lower applied voltages. We demonstrate the wide applicability of our responsive, fault-tolerant films by using our system for adjustable transparency films, tunable diffraction gratings, and a dynamic surface template/factory from which various static micropatterns can be molded on demand.

Crystallization of perovskite structure chromites (ACrO

The diagnostic accuracy of medullary carcinoma is very high because it commonly presents characteristic features, including a dispersed cell pattern formed by pleomorphic cells with extremely eccentric nuclei that contain coarsely granular to salt-pepper-type chromatin. However, medullary carcinoma cells sometimes demonstrate a monomorphic cell pattern, comprised exclusively of plasmacytoid cells with abundant eosinophilic cytoplasm and sharing strong similarity with oxyphilic cell neoplasms, thus constituting the important diagnostic pitfalls. A distinction between Hurthle cell neoplasm and medullary carcinoma can be made by the extremely marginal location of the nuclei with coarsely granular to salt-pepper-type chromatin for the medullary carcinoma cells and prominent macronucleoli for the Hurthle cells. Sometimes apparent cytoplasmic granularity could be observed in Hurthle cells, which is different from the fibrillar cytoplasm of medullary carcinoma cells with wet-fixation hematoxylin-eosin-stained preparation.

Summary Zeolitic imidazolate frameworks (ZIFs) have been widely investigated for their use in separation, gas adsorption, catalysis, and biotechnology. Their practical applications, however, can be hampered by their structural instability in humid acidic conditions. Here, guided by density functional theory calculations, we demonstrate that the acidic stability of two polymorphic ZIFs (i.e., ZIF-8 and ZIF-L) can be enhanced by the incorporation of functional groups on polypeptides or DNA. A range of complementary synchrotron investigations into the local chemical structure and bonding environment suggest that the enhanced acidic stability arises from the newly established coordinative interactions between the Zn centers and the inserted carboxylate (for polypeptides) or phosphate (for DNA) groups, both of which have lower pKas than the imidazolate ligand. With functional biomolecular homologs (i.e., enzymes), we demonstrate a symbiotic stability reinforcement effect, i.e., the encapsulated biomolecules stabilize the ZIF matrix while the ZIF exoskeleton protects the enzyme from denaturation.

Some of the characteristic features of subacute or granulomatous thyroiditis overlap with those of a papillary thyroid carcinoma, especially the presence of large giant cells. It is important to realize that the presence of numerous multinucleated giant cells does not rule out the diagnosis of papillary thyroid carcinoma. In this instance, the key for differential diagnosis is not to miss the rarely existed tissue fragment of follicular cells with characteristic nuclear features of papillary thyroid carcinoma. Clean background, almost without inflammatory cells admixed, and “bubble gum” colloid as well as the presence of two types of multinucleated giant cells are not in favor of the diagnosis of subacute thyroiditis.

Hurthle cell neoplasms have been cytologically placed in a category distinct from follicular neoplasms in our past experience. Cytological features of hematoxylin-eosin-stained specimens diagnosed as “suspected Hurthle cell neoplasms” include that the aspirate is generally high cellular, is comprised exclusively of Hurthle cells, has well-defined cell borders with enlarged nuclei, has abundant granular cytoplasm, and has round, oval to polygonal nuclei sometimes with prominent macronucleoli. The background is usually clean or bloody with or without histiocytes. Hurthle cell metaplasia of follicular cells is seen in several conditions affecting the thyroid, displaying a range of cytological features that mimic those encountered in Hurthle cell neoplasms, constituting important diagnostic pitfalls. An admixture of regular follicular cells, oncocytes with highly pleomorphic in size, transition forms, degenerative changes with histiocytes, lymphocytes or colloid in the background, absent macronucleus could serve as the clues to the diagnosis of nonneoplastic Hurthle cell nodules.

The nuclei of the oxyphilic or non-oxyphilic follicular epithelium in Hashimoto’s thyroiditis often exhibit considerable nuclear atypia, showing a range of nuclear changes that mimic those encountered in papillary thyroid carcinoma. Syncytial tissue fragments with or without any architectural configurations; enlarged nuclei with finely granular, powdery, or watery chromatin and nuclear contour irregularity; nuclear pseudoinclusions; nuclear grooves; and multiple micro- and/or macronucleoli could be applicable as the minimal criteria for the cytological diagnosis of papillary carcinoma. It is essential to remain in conservative diagnosis until the minimal criteria of papillary thyroid carcinoma is fulfilled. One single cytological feature of papillary carcinoma proves to be meaningless to conclude malignancy in Hashimoto’s thyroiditis since Hashimoto’s thyroiditis shows several overlapping features with papillary carcinoma.

In recent years, the safe and stable operation of electrified railways has attracted more and more attention. In particular, the stability of vehicle-grid coupling, which focuses on the phenomenon of vehicle-grid high frequency resonance (HFR), has become a hot research topic. Based on the instability mechanism of vehicle-grid coupling, and from the perspective of grid-side converter modulation strategy, measures to suppress HFR are further proposed. Based on the improvement of commonly used modulation strategies, Periodic Control Carrier Phase-Shift Pulse Width Modulation (PCCPS-PWM) is proposed, this solves the HFR problem caused by the switching characteristic frequency harmonics caused by the inaccurate phase shift angle between the grid-side converters. And it is verified by Matlab simulation and hybrid electric train sets.

In order to study the laws of surface subsidence due to mining coal under thick alluvium of Quandian mine, two survey lines were designed on the surface above the first face. By analyzing the position of the maximum subsidence point of the tendency survey line, the zenith angle was obtained, and the correctness of taking bedrock thickness instead of average mining depth to design the position of the trend survey line in the mining area was confirmed; and based on the analyses of the measured data, the critical size of the gob full opening in the geological and mining conditions didn't follow the general law that the gob would reach the critical size when the panel has moved for a distance of 1.2H0 - 1.4H0. These results showed that the bedrock played a major role in the spread of whole overburden subsidence in the geological and mining conditions, while the loose layer had less affection. In addition, based on the analyses of the measured data, some rock movement parameters and probability integral prediction parameters of the surface subsidence of Quandian mine in the geological and mining conditions have been obtained. The study would have some important theoretical significance and practical guidance for implementing mining beneath buildings, water bodies and railways and prevent of this coal field as well as surface structure damage control.

Poly(3,4-ethylenedioxythiophene) (PEDOT) is formed inside a metal–organic framework (MOF). MOF removal leads to sub-millimetre structures of the nanostructured conducting polymer., Reactions inside the pores of metal–organic frameworks (MOFs) offer potential for controlling polymer structures with regularity to sub-nanometre scales. We report a wet-chemistry route to poly-3,4-ethylenedioxythiophene (PEDOT)–MOF composites. After a two-step removal of the MOF template we obtain unique and stable macroscale structures of this conductive polymer with some nanoscale regularity.

Through quick, accurate and non-contact scan, Terrestrial 3D Laser Scanner can get high density point cloud data. But limited by the scanning range, Terrestrial 3D Laser Scanner could not finish scanning data at one time. Therefore, in order to reconstruct a three-dimensional model of the object, we must get the point cloud data from different perspectives; Next, finish the registration of the multi-view point data; Finally, realize the 3D visualization. The point cloud data registration is the key to the 3D visualization of complete object. Traverse survey is proposed as a new point cloud data registration method in this paper, this method is based on traversing principle, according to the conventional control survey, synchronization of scanning and control measure can be realized, and the efficiency of the Terrestrial 3D Laser Scanner will be improved. By comparing the result of different methods, the mean square error of a point got by the traverse survey data registration method is equally distributed and not affected by the time of registration. So, the point cloud data registration of traverse survey is with certain operability.

ZnO nanostructures were fabricated into flower-like nanoscale arrays by the hydrothermal growth of ZnO nanowires onto a self-assembled monolayer of polystyrene spheres on a glass substrate. Fluorescent molecules conjugated with streptavidin were incubated on glass with 3-(glycidoxypropyl) trimethoxysilane (GPTS) modified and biotinylated bovine serum albumin (bBSA) attached (GPTS–bBSA), aligned ZnO nanorod arrays and ZnO nanoflower arrays, respectively. An enhancement factor of up to 45 was obtained from ZnO nanoflower arrays, compared to less than 10 for the aligned nanorods. More importantly, using the same substrate, we observed a broadband fluorescence enhancement. The level of enhancement obtained from the nanoflower arrays is comparable with that from Metal Enhanced Fluorescence. The broadband nature of this process makes it an attractive alternative for fluorescent based device development.

In the base of the detailed analysis of dam safety monitoring expert system of knowledge, it is introduced that the method of expert system structure of knowledge and the characteristics of knowledge’s representation. Maxing the method and ANN to indicate dam safety and the physical structure of the knowledge base is studied. The reasoning strategy based on hybrid knowledge base is also discussed and the technical’s problems which forming mixing knowledge base should be paid attention to is analysed.

Genetic algorithm is a kind of random searching algorithm which utilizes natural selection and natural heritage mechanism. The main character of it is a strategy of group searching and information exchange among the individuals of a group, the search does not depend on gradient information. Combining the genetic algorithm with the neural network intelligent technology, utilizing neural network model and regarding genetic algorithm as weight evolutionary algorithm for GPS height conversion, this paper puts forward the basic ideas and realizing process. With the explanation of an example, the results shows that the algorithm used to convert the GPS height has better precision and certain practical value.

Bisphosphonates have been used to treat many bone diseases in clinic. Bisphosphonates have also been proven useful in the management of bone metastasis in patients with breast and prostate carcinoma as demonstrated in a number of trials in vitro and in vivo, but, it is little known that the effect of bisphosphonates on lung cancer, one of the most common bone metastatic malignant tumors. This study is to investigate the effect of several bisphosphonates on inhibiting proliferation of different lung cancer cell lines in vitro, and to validate whether this inhibitive effect is comprehensive or selective.The cytotoxic effect of bisphosphonates on lung cancer cells and human normal liver cells was determined by sulforhodamine B (SRB) assay.After incubation of lung cancer cells with bisphosphonates for 72h, the proliferation was inhibited in different degrees. The inhibiting activity of medronate (MDP) was the lowest, while the activity of ibandronate and incadronate (YM175) was between MDP and alendronate. The effects of bisphosphonates on human normal liver cells were different. The toxicity of MDP, ibandronate and YM175 was low, while alendronate had high toxicity. The sensitivity of lung cancer cells to bisphosphonates was also different. The sensitivity of H446 and SPC-A1 was comparatively lower, while H460 and A549 were more sensitive.Bisphosphonates can inhibit the proliferation of lung cancer cells and human normal liver cells in different degrees. The inhibiting effect is associated with the kind and concentration of bisphosphonates, and also the kind of lung cancer cells.

We developed an immunopathological staining of LAM-B antigen in formalin-fixed paraffin-embedded tissues, and compared it with, PGL-I immunostaining, Fite Faraco's stain and periodic acid carbol pararosaniline (PACPR) stain. Out of the total 28 leprosy cases, 27 were positive to LAM-B immunostaining while 23 were positive to PGL-I stain. Fite's stain was positive in 21 cases while PACPR stain was positive in 24 cases. In scrofuloderma, LAM-B antigen was observed only in the granuloma while no other positive findings were noted with other stains. Normal skin did not give any positive findings with any of the stains. Other dermatoses showed no positive findings to any of the stains tested. LAM-B staining was observed in the nerve even in the absence of bacilli in leprosy tissues. Presence of LAM-B in the cutaneous nerves is helpful in discriminating leprosy from other mycobacterioses. Considering the high sensitivity of LAM-B and the predilection of M. leprae for the nerves, we concluded that LAM-B staining can be a useful new tool in the prompt diagnosis of leprosy, especially in suspected or early cases.