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This work is dedicated to improving the efficient purification, collection, and clumped isotope analysis method for natural methane with a wide range of concentrations.

The spintronic properties of molecules are essential for the development of multifunctional organic spintronic devices. Here, the spin polarization of bis-(8-hydroxyquinoline) zinc (Znq2) molecule upon electron and hole injection has been theoretically studied by using density-functional theory calculations. It is found that both the injected excess electrons and holes are highly spin polarized in Znq2, leading to an approximately linearly increased magnetic moments with the amount of the charge injected. Our calculation also reveals that the spin polarization upon excess electron and hole injection may attribute to the exchange splitting of lowest unoccupied molecular orbital (LUMO)-related p states of N and C atoms of pyridyl rings and the highest occupied molecular orbital (HOMO)-related p states of O and C atoms of the phenoxide rings, respectively. The d0 ferromagnetism in the charge-injected Znq2 molecule is quite promising for organic spintronic devices.

The strongly supervised deep convolutional neural network (DCNN) has better performance in assessing breast cancer (BC) because of the more accurate features from the slice-level precise labeling compared with the image-level labeling weakly supervised DCNN. However, manual slice-level precise labeling is time consuming and expensive. In addition, the slice-level diagnosis adopted in the DCNN system is incomplete and defective because of the lack of other slices’ information. In this paper, we studied the impact of the region of interest (ROI) and lesion-level multi-slice diagnosis in the DCNN auxiliary diagnosis system. Firstly, we proposed an improved region-growing algorithm to generate slice-level precise ROI. Secondly, we adopted the average weighting method as the lesion-level diagnosis criteria after exploring four different weighting methods. Finally, we proposed our complete system, which combined the densely connected convolutional network (DenseNet) with the slice-level ROI and the average weighting lesion-level diagnosis after evaluating the performance of five DCNNs. The proposed system achieved an AUC of 0.958, an accuracy of 92.5%, a sensitivity of 95.0%, and a specificity of 90.0%. The experimental results showed that our proposed system had a better performance in BC diagnosis because of the more precise ROI and more complete information of multi-slices.

As one of the most important narrow bandgap ternary semiconductors, GaAs1−xSbx nanowires (NWs) have attracted extensive attention recently, due to the superior hole mobility and the tunable bandgap, which covers the whole near-infrared (NIR) region, for technological applications in next-generation high-performance electronics and NIR photodetection. However, it is still a challenge to the synthesis of high-quality GaAs1−xSbx NWs across the entire range of composition, resulting in the lack of correlation investigation among stoichiometry, microstructure, electronics, and NIR photodetection. Here, we demonstrate the success growth of high-quality GaAs1−xSbx NWs with full composition range by adopting a simple and low-cost surfactant-assisted solid source chemical vapor deposition method. All of the as-prepared NWs are uniform, smooth, and straight, without any phase segregation in all stoichiometric compositions. The lattice constants of each NW composition have been well correlated with the chemical stoichiometry and confirmed by high-resolution transmission electron microscopy, X-ray diffraction, and Raman spectrum. Moreover, with the increase of Sb concentration, the hole mobility of the as-fabricated field-effect-transistors and the responsivity and detectivity of the as-fabricated NIR photodetectors increase accordingly. All the results suggest a careful stoichiometric design is required for achieving optimal NW device performances.

Recently, the demand for semi-transparent perovskite solar cells (SPSCs) to serve as semitransparent windows for urban building and automobile applications has grown. However, it is challenging to prepare high-quality ultra-thin perovskite films, significantly restricting the development of SPSCs. In this paper, we report an all-round performance improvement of ultra-thin perovskite films and SPSCs prepared by using a thermal-pressed recrystallizing (TPR) method. The average grain size of perovskite films increased from ∼340 nm to ∼1.64 μm, after the TPR treatment, along with a dramatic decrease in the surface root mean square (RMS) roughness from ∼14.9 nm to ∼1.04 nm. The SPSCs fabricated by the TPR method showed a significant improvement in all-round performance, such as open-circuit voltage, short-circuit current, fill factor, power conversion efficiency, transmittance and stability. The average power conversion efficiency showed a significant increase of up to 32.8% after TPR treatment, indicating the potential for the development of high performance semitransparent photovoltaic windows.

Based on temporal-multiplexing, super multi-view (SMV) technology gets implemented on a near-eye three-dimensional (3D) display, successfully overcoming the vergence accommodation conflict (VAC). The proposed system has two eyepieces for two eyes, respectively, each of which is constructed by an organic light-emitting diode (OLED) micro-display, a projecting lens, and a gating-aperture array. The gating-aperture arrays, consisting of gating apertures with an interval smaller than the diameter of the viewer’s pupil, are attached to the projecting lenses and gate different spatial segments of the projecting lens’s exit aperture in time sequence. Through refreshing the corresponding display contents synchronously, two or more light rays passing through a displayed point are guided by the gating-aperture array into each eye sequentially. Based on the persistence of vision, these light rays converge into a spatial light spot that the eye can focus on naturally, thus enabling a consistence between focusing distance and convergence distance. Further, gating-aperture array with polarization characteristics is designed to get a larger field of view (FOV), accompanied by a half-wave variable retarder being inserted between the OLED micro-display and the gating-aperture array in each eyepiece. Employing two OLED micro-displays of 120-Hz frame rates, a near-eye 3D display prototype has been demonstrated with an FOV 40 deg and a display frequency of 40 Hz, being free from VAC.

The relative low hole mobility of p-channel building block device challenges the continued miniaturization of modern electronic chips. Metal-semiconductor junction is always an efficient strategy to control the carrier concentration of channel semiconductor, benefiting the carrier mobility regulation of building block device. In this work, complementary metal oxide semiconductor (CMOS)-compatible metals are selected to deposit on the surface of the important p-channel building block of GaSb nanowire field-effect-transistors (NWFETs), demonstrating the efficient strategy of hole mobility enhancement by metal-semiconductor junction. When deposited with lower work function metal of Al, the peak hole mobility of GaSb NWFET can be enhanced to as high as ≈3372 cm2 V-1 s-1 , showing three times than the un-deposited one. The as-studied metal-semiconductor junction is also efficient for the hole mobility enhancement of other p-channel devices, such as GaAs NWFET, GaAs film FET, and WSe2 FET. With the enhanced mobility, the as-constructed CMOS inverter shows good invert characteristics, showing a relatively high gain of ≈18.1. All results may be regarded as important advances to the next-generation electronics.

A facile one-step electrochemical etching based on NaNO3 solution was developed for use in the chemical lift-off nanoporous- (NP-) GaN distributed Bragg reflectors (DBRs) over a macroscopic area (>1 cm2). The reflectivity of the lift-off DBR mirror is ~85%, which is far lower than that (~97%) of the NP-GaN DBR on the sapphire substrate. The decrease should be attributed to light scattering due to higher roughness in the lift-off mirror. To study its possible applications, tris(8-hydroxyquinoline) aluminum (III) (Alq3) thin film was grown on transferred NP-GaN DBR mirror onto silicon substrate via a thermal evaporation deposition. Compared to the reference Alq3 thin film, the photoluminescence of the Alq3 thin film on the transferred mirror presents significant enhancement and slight blue-shift, which should be attributable to reflectivity enhancement by the DBR and inner channel surface in the DBR mirror, respectively.

Weak n-type characteristics or poor p-type characteristics are limiting the applications of binary semiconductors based on ambipolar field-effect transistors (FETs). In this work, a ternary alloy of In0.2Ga0.8As nanowires (NWs) is successfully prepared using a Ni catalyst during a typical solid-source chemical-vapor-deposition process to balance the weak n-type conduction behavior in ambipolar GaAs NWFETs and the poor p-type conduction behavior in ambipolar InAs NWFETs. The presence of ambipolar transport, contributed by a native oxide shell and the body defects of the prepared In0.2Ga0.8As NWs, is confirmed by the constructed back-gated NWFETs. As demonstrated by photoluminescence, the bandgap of the prepared In0.2Ga0.8As NWs is 1.28 eV, offering the promise of application in near-infrared (NIR) photodetection. Under 850 nm laser illumination, the fabricated ambipolar NWFETs show extremely low dark currents of 50 pA and 0.5 pA when positive and negative gate voltages are applied, respectively. All the results demonstrate that with careful design of the surface oxide layer and the body defects, NWs are suitable for use in next-generation optoelectronic devices.

Background We aimed to evaluate a deep learning (DL) model combining perinodular and intranodular radiomics features and clinical features for preoperative differentiation of solitary granuloma nodules (GNs) from solid lung cancer nodules in patients with spiculation, lobulation, or pleural indentation on CT. Patients and Methods We retrospectively recruited 915 patients with solitary solid pulmonary nodules and suspicious signs of malignancy. Data including clinical characteristics and subjective CT findings were obtained. A 3-dimensional U-Net-based DL model was used for tumor segmentation and extraction of 3-dimensional radiomics features. We used the Maximum Relevance and Minimum Redundancy (mRMR) algorithm and the eXtreme Gradient Boosting (XGBoost) algorithm to select the intranodular, perinodular, and gross nodular radiomics features. We propose a medical image DL (IDL) model, a clinical image DL (CIDL) model, a radiomics DL (RDL) model, and a clinical image radiomics DL (CIRDL) model to preoperatively differentiate GNs from solid lung cancer. Five-fold cross-validation was used to select and evaluate the models. The prediction performance of the models was evaluated using receiver operating characteristic and calibration curves. Results The CIRDL model achieved the best performance in differentiating between GNs and solid lung cancer (area under the curve [AUC] = 0.9069), which was significantly higher compared with the IDL (AUC = 0.8322), CIDL (AUC = 0.8652), intra-RDL (AUC = 0.8583), peri-RDL (AUC = 0.8259), and gross-RDL (AUC = 0.8705) models. Conclusion The proposed CIRDL model is a noninvasive diagnostic tool to differentiate between granuloma nodules and solid lung cancer nodules and reduce the need for invasive diagnostic and surgical procedures.

The surface Fermi level pinning effect promotes the formation of metal-independent Ohmic contacts for the high-speed GaSb nanowires (NWs) electronic devices, however, it limits next-generation optoelectronic devices. In this work, lead-free all-inorganic perovskites with broad bandgaps and low work functions are adopted to decorate the surfaces of GaSb NWs, demonstrating the success in the construction of Schottky-contacts by surface engineering. Benefiting from the expected Schottky barrier, the dark current is reduced to 2 pA, the I

Exciplex-type thermally activated delayed fluorescence (TADF) materials exhibit charming application potential in organic light-emitting diodes. However, investigations on their non-linear optical properties are rather rare. Here, we report up-conversion fluorescence from an electron donor-acceptor exciplex blend composed of the donor 4,4′,4″-Tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine (m-MTDATA) and the acceptor 1,3,5-Tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi). Strong up-conversion fluorescence has been observed and a two-photon absorption (TPA) cross-section σ of ∼387 GM has been measured. The optical spectra analysis indicates that the TPA is dominated by the exciton absorption of m-MTDATA molecules. The observed up-conversion fluorescence is explained by a joint mechanism including two-photon absorption, exciplex formation, reverse intersystem crossing, and prompt or delayed fluorescence. The TADF and up-conversion fluorescence properties of this exciplex blend have great application potentials in linear and non-linear optics.

Breast segmentation and mass detection in medical images are important for diagnosis and treatment follow-up. Automation of these challenging tasks can assist radiologists by reducing the high manual workload of breast cancer analysis. In this paper, deep convolutional neural networks (DCNN) were employed for breast segmentation and mass detection in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). First, the region of the breasts was segmented from the remaining body parts by building a fully convolutional neural network based on U-Net++. Using the method of deep learning to extract the target area can help to reduce the interference external to the breast. Second, a faster region with convolutional neural network (Faster RCNN) was used for mass detection on segmented breast images. The dataset of DCE-MRI used in this study was obtained from 75 patients, and a 5-fold cross validation method was adopted. The statistical analysis of breast region segmentation was carried out by computing the Dice similarity coefficient (DSC), Jaccard coefficient, and segmentation sensitivity. For validation of breast mass detection, the sensitivity with the number of false positives per case was computed and analyzed. The Dice and Jaccard coefficients and the segmentation sensitivity value for breast region segmentation were 0.951, 0.908, and 0.948, respectively, which were better than those of the original U-Net algorithm, and the average sensitivity for mass detection achieved 0.874 with 3.4 false positives per case.

Near-infrared two-photon absorption (TPA) molecules designed based on intramolecular charge-transfer (CT) interactions have been widely investigated during the last few decades; however, studies on supramolecular TPA materials based on intermolecular CT interactions are quite rare. In this work, cocrystals of acridine and 1,2,4,5-tetracyano-benzene were successfully prepared by self-assembly. The cocrystals show yellow emission centered at ∼540 nm with a solid-state photoluminescence quantum yields (PLQY) of 22.48%. Two-photon excited fluorescence (TPEF) measurements show that the cocrystals display wide-window TPEF that is absent in their individual components. Optical absorption analysis indicate that the fluorescence is originated from excitation from the ground states to CT exciton states instead of exciton states of donor or acceptor molecules. This work may facilitate further two-component nonlinear optical material design and applications.

With strip-type timing-apertures attached to each eye of a viewer, more than one perspective views can be guided to either eye sequentially through different timing-apertures, thus implementing VAC-free (vergence-accommodation conflict-free) SMV (Super Multi-view) 3D (three-dimensional) display. To overcome the FOV (field of view) limitation problem due to small size of the timing-apertures along their arrangement direction, novel polarization architectures are designed to the timing-apertures in this paper. Correspondingly, the display screen of the proposed SMV display system is divided into M > 1 sub-screens along the arrangement direction of the timing-apertures, with adjacent sub-screens emitting light of mutually orthogonal polarization. At a time-point of each time period, a group of M timing-apertures, which correspond to the M sub-screens in a one-by-one manner along the arrangement direction, are turned on for creating an M-fold FOV, with each polarized timing-aperture of the group allowing light from the corresponding sub-screen passing through and blocking light from sub-screen(s) adjacent to the corresponding sub-screen. At 2T > 1 time-points of each time period, 2T groups of timing-apertures are turned on sequentially for presenting more than one two-dimensional images of the displayed scene to each eye, to implement SMV display based on persistence of vision. M stands for the FOV magnification number and T stands for the two-dimensional image number for each eye. As proof, a 3-fold FOV of 41° gets implemented experimentally with a currently available timing-aperture array of M = 3, accompanied by an effective noise-free region (ENFR) of 8.34 mm. Furthermore, the promising of freeing FOV from timing-aperture constraint fundamentally by larger M is described, out-of-screen blur along strip direction of the timing-apertures and the problem of limited ENFR are discussed.

One-dimensional tubular structures of organic small molecules are almost lacking from the field of nanomaterials and devices despite the vast number of species used, and their excellent electronic, optical, and electrochemical properties. Very few organic small molecules have been fabricated into hollow structures, such as microcages, nanotubes, and nanorings. In this study, we developed a one-step and energy-saving method for synthesizing tris(8-hydroxyquinoline)aluminum (Alq3) microtubes. The structures and waveguide properties of the Alq3 microtubes were also studied. This new and facile method for fabricating organic small molecules with nitrogen-rich heteroatoms may stimulate further investigations of the performance of tubular structures.

Binary organic crystals play critical roles in ambipolar transistors, solar cells, and light-emitting devices. However, these crystals are currently limited to a few planar materials and fixed stoichiometric ratios. Here, a new strategy of binary organic crystals was demonstrated by preparing alloy-like organic single crystals. Binary crystals based on nonplanar 8-hydroxyquinoline metallic complexes were successfully self-assembled through a solution pathway at room temperature. Structural analyses exhibit that the samples are rod-shaped homogeneous mixed crystals. We show that the stoichiometric ratio of the crystals can be arbitrarily adjusted by changing the ratio of the component materials. The charge-transfer (CT) interaction and photophysical properties were also studied. Our strategy of organic crystals may facilitate the development of binary or solid-solution organic crystals with precisely adjusted structures and physical properties.

The solid-to-solid crystallization processes of organic molecules have been poorly understood in view of the complexity and the instability of organic crystals. Here, we studied the crystallization of a π-conjugated small molecular semiconductor, bis-(8-hydroxyquinoline) copper (CuQ2), by annealing the thin films at different temperatures. We observed a classical film-to-nanorods crystallization at 80 °C, a coexistence of classical and nonclassical nucleation and particle growth at 120 °C, and a nonclassical crystal growth at 150 °C. We found that the growth of the crystals followed the following processes: particle nucleation, particle growth, particle migration, nondirectional particle attachment, and structure reconstruction. We notice that the growth of CuQ2 particles follows an outside-to-inside process. More interestingly, our experiments suggest that the submicron CuQ2 particles are able to migrate dozens of micrometers at 150 °C.

The development of room temperature organic magnets is long viewed as great challenge in chemistry, physics, materials science, and spintronics. Here, room temperature ferromagnetic properties of rare earth Sm-doped tris(8-hydroxyquinoline) gallium (GaQ3) molecular thin films prepared by thermally co-evaporating Sm metals and GaQ3 powders were reported. X-ray photoelectron spectrometer, Fourier transform infrared spectroscopy and density functional theory analysis suggest that the doped Sm atom bonds with N atoms on different hydroxyquinoline ligands. The room temperature ferromagnetism is attributed to the extremely large energy difference (594 meV) between the ferromagnetic ground state and the antiferromagnetic state. Furthermore, photoluminescence experiments show that the films emit green light at room temperature. Our experiments may be helpful for the development of molecular ferromagnetic optoelectronic materials for the use of novel multifunctional optoelectronic and spintronic devices.

Exciplex organic light-emitting diodes (XOLEDs) utilize nonemissive triplet excitons via a reverse intersystem crossing process of thermally activated delayed fluorescence. The small energy difference between the lowest singlet and triplet levels of exciplex also allows a magnetic field to manipulate their populations, thereby achieving ultralarge “intrinsic” magneto-electroluminescence (MEL) in XOLEDs. Here we incorporate it into a hybrid type of spintronic device (“hybrid spin-XOLED”), where the XOLED is connected to a magnetic tunnel junction with large magnetoresistance, to introduce an “extrinsic” MEL response that interferes with the “intrinsic” MEL. The ratio between two MEL contributions, the MEL value, and the field response were altered by changing the exciplex layer thickness or actively manipulated by adding another current source that drives the XOLED. Most importantly, by involving two XOLEDs (green and red) in the same circuit, the hybrid spin-XOLED shows a color change when sweeping the ma...

The blood-brain barrier is a formidable obstacle for glioma chemotherapy due to its compact structure and drug efflux ability. In this study, a dual-targeting drug delivery system involving Angiopep-2-conjugated biodegradable polymersomes loaded with doxorubicin (Ang-PS-DOX) was developed to exploit transport by the low-density lipoprotein receptor-related protein 1 (LRP1), which is overexpressed in both blood-brain barrier and glioma cells. The polymersomes (PS) were prepared using a thin-film hydration method. The PS were loaded with doxorubicin using the pH gradient method (Ang-PS-DOX). The resulting PS were uniformly spherical, with diameters of ~135 nm and with ~159.9 Angiopep-2 molecules on the surface of each PS. The drug-loading capacity and the encapsulation efficiency for doxorubicin were 7.94%±0.17% and 95.0%±1.6%, respectively. Permeability tests demonstrated that the proton diffusion coefficient across the PS membrane was far slower than that across the liposome membrane, and the common logarithm value was linearly dependent on the dioxane content in the external phase. Compared with PS-DOX, Ang-PS-DOX demonstrated significantly higher cellular uptake and stronger cytotoxicity in C6 cells. In vivo pharmacokinetics and brain distribution experiments revealed that Ang-PS-DOX achieved a more extensive distribution and more abundant accumulation in glioma cells than PS-DOX. Moreover, the survival time of glioma-bearing rats treated with Ang-PS-DOX was significantly prolonged compared with those treated with PS-DOX or a solution of free doxorubicin. These results suggested that Ang-PS-DOX can target glioma cells and enhance chemotherapeutic efficacy.

Two-photon excited fluorescence materials usually suffer from inefficient two-photon absorption (TPA) and nonradiative excited states. Here, upconversion fluorescence in an electron donor-acceptor (DA) exciplex doped with fluorescent emitters are systematically investigated. It has been found that the undoped DA exciplex exhibits enhancements of ∼129% and ∼365% in upconversion fluorescence compared to donor- and acceptor-only systems, respectively. Interestingly, photoluminescence quantum yields (PLQYs) up to ∼98.65% were measured and immensely enhanced upconversion fluorescence was observed after doping various fluorescent emitters into the DA exciplex. Our results reveal the existence of two-photon excited energy harvesting in a thermally activated delayed fluorescence (TADF) DA exciplex doped with fluorescent emitters, via reverse intersystem crossing followed by rapid Förster resonance energy transfer. Moreover, the additional gain mechanism related to intermolecular CT interaction that occurs at the TPA stage is found in the TADF DA exciplex system.

Exciplex-based thermally activated delayed fluorescence (TADF) materials show long luminescence lifetimes and high quantum efficiency by converting the non-radiative triplets into the radiative singlets. Here, strong upconverted fluorescence from the amorphous thin films of TADF donor-acceptor (D-A) exciplexes is observed under near-infrared excitation. The spectroscopic studies demonstrate that the enhanced upconversion in exciplex emission combines a series of excited state processes including the two-photon absorption (TPA) of donors and the TADF of D-A pairs. The comparison between donor-only and D-A systems indicates that the upconversion is greatly facilitated by the energy harvesting mechanisms existing in the exciplex-based TADF materials. The results reveal the formation mechanism of exciplex excited-states following the two-photon excitation in D-A blends, and consequently the potentials of exciplex materials in nonlinear optics applications. Moreover, a maximum D-A distance of ~6.9 nm for two-photon excited exciplex formation is obtained.

We report the controllable growth of rice-shape nanoparticles of Alq3 by an extremely facile self-assembly approach. Possible mechanisms have been proposed to interpret the formation and controlled process of the single crystal nanoparticles. The field-emission performances (turn-on field 7 V μm−1, maximum current density 2.9 mA cm−2) indicate the potential application on miniaturized nano-optoelectronics devices of Alq3-based. This facile method can potentially be used for the controlled synthesis of other functional complexes and organic nanostructures.

A new type of organic light-emitting diode (OLED) has emerged that shows enhanced operational stability and large internal quantum efficiency approaching 100%, which is based on thermally activated delayed fluorescence (TADF) compounds doped with fluorescent emitters. Magneto-electroluminescence (MEL) in such TADF-based OLEDs and magneto-photoluminescence (MPL) in thin films based on donor–acceptor (D–A) exciplexes doped with fluorescent emitters with various concentrations are investigated. It has been found that both MEL and MPL responses are thermally activated with substantially lower activation energy compared to that in the pristine undoped D–A exciplex host blend. In addition, both MPL and MEL steeply decrease with the emitter's concentration. This indicates the existence of a loss mechanism, whereby the triplet charge-transfer state in the exciplex host blend may directly decay to the lowest, nonemissive triplet state of the fluorescent emitter molecules.

Room temperature ferromagnetism was observed in rare earth dysprosium (Dy)-doped tris(8-hydroxyquinoline) aluminum (Alq3) organic small molecular films. The Dy-doped Alq3 films were prepared by co-evaporating pure Alq3 and Dy powders on Si substrates in a vacuum. The maximum room temperature coercive field and the saturation magnetization are about 70 Oe and 9.5 × 10−6 emu, respectively. The structures were studied by the atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and synchrotron radiation X-ray absorption fine structure (XAFS). The magnetic properties were investigated by the MicroMag Alternating Gradient Magnetometer (AGM), Quantum Design superconducting quantum interference device (SQUID) and first-principles calculations. The room temperature ferromagnetism is ascribed to the magnetic moments induced by the Dy atom and the large energy difference between ferromagnetic and antiferromagnetic coupling.

First-principles calculations based on spin density-functional theory (DFT) have been performed to study the magnetic properties of Al-doped tris(8-hydroxyquinoline) cobalt (CoQ 3 ). The results show that pure CoQ 3 molecule is nonmagnetic and the Co atom carries no magnetic moment. The Al dopants give birth to spontaneous spin polarization in CoQ 3 molecules, which localized mainly on the 3 d orbitals of Co atom. The origin of magnetic moments is due to the charge transfers from Al atom to CoQ 3 molecule.

Room temperature ferromagnetic properties were obtained in an originally paramagnetic molecule bis(8-hydroxyquinoline)cobalt (Coq 2 ) by doping a nonmagnetic element aluminum. The Al-doped Coq 2 films with the thicknesses of about 200 nm were prepared on Si substrates by co-evaporating pure Coq 2 powders (99%) and Al wires (99%) simultaneously at a base pressure of 1.9×10 −4 Pa. The magnetic properties of the films were measured at different temperatures by using a Quantum Design superconducting quantum interference device (SQUID). The obtained maximum coercive field is about 250 Oe at 300 K. The electronic structures of Al-doped Coq 2 were studied by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) analysis. The FTIR and XPS spectra indicate that the doped Al atoms prefer to interact with N and O atoms in Coq 2 molecules. XAFS analysis shows that the Coq 2 molecule does not decompose during the co-evaporating process. The ferromagnetism of the film is attributed to the interactions between Al and N p states in lowest unoccupied molecular orbitals (LUMO).

The structural, electronic and magnetic properties of 8-hydroxyquinoline-based small molecules TMQ x (TM=Cr, Mn, Fe, Co, Ni, Cu and Zn, and x =2 or 3) are systemically studied from first principles. These small molecules are spin-polarized semiconductors except for NiQ 2 , ZnQ 2 , and CoQ 3 . For TMQ 2 , the magnetic moments can be expressed as 8- nµ B ( n is the number of 3 d electrons of TM ions. For Mn, Fe, Co, and Ni, n =5, 6, 7, and 8 respectively) and 10- nµ B ( n =9 and 10 for Cu and Zn, respectively). For TMQ 3 , the magnetic moments can be expressed as 6- nµ B ( n =3, 4, 5, 6 for Cr, Mn, Fe, and Co, respectively). The magnetism can be explained by the spin-polarized filling of splitting d orbitals on the basis of the crystal field theory. This provides theoretical insight for better understanding of 8-hydorquinoline-based complexes (TMQ x ).

Ultra-long crystalline Alq3 1 dimensional (1D) materials were prepared by using an extremely facile solution approach without any surfactant, SDS, anti-solvent, or other reagents. The Alq3 1D materials have smooth surfaces and pentagonal or hexagonal cross-sections. The length of the microrods have α-phase crystalline structures. The prepared Alq3 samples exhibit excellent green-light photoluminescence (PL) performance. The growth mechanism of the Alq3 1D structures were discussed. The limitation conditions of the Alq3 microrods were also studied. In addition, the influence of the volume of CHCl3 on the microrods was discussed. This controllable growth method can potentially be extended to other functional organic nanomaterials.

We report for the first time the controllable growth of tubular nanostructures at the nanoscale of the broadly applied organic drug material, tris(8-hydroxyquinoline)gallium (Gaq3), by an extremely facile approach. The products show a relatively low turn-on field (8.5 V μm−1) and a very high maximum current density (2.3 mA cm−2). The length of the Gaq3 tubes and nanostructures can be readily manipulated and the adopted method is highly transferrable to other organic materials.

The blood–brain barrier is a formidable obstacle for glioma chemotherapy due to its compact structure and drug efflux ability. In this study, a dual-targeting drug delivery system involving Angiopep-2-conjugated biodegradable polymersomes loaded with doxorubicin (Ang-PS-DOX) was developed to exploit transport by the low-density lipoprotein receptor-related protein 1 (LRP1), which is overexpressed in both blood–brain barrier and glioma cells. The polymersomes (PS) were prepared using a thin-film hydration method. The PS were loaded with doxorubicin using the pH gradient method (Ang-PS-DOX). The resulting PS were uniformly spherical, with diameters of ~135 nm and with ~159.9 Angiopep-2 molecules on the surface of each PS. The drug-loading capacity and the encapsulation efficiency for doxorubicin were 7.94%±0.17% and 95.0%±1.6%, respectively. Permeability tests demonstrated that the proton diffusion coefficient across the PS membrane was far slower than that across the liposome membrane, and the common logarithm value was linearly dependent on the dioxane content in the external phase. Compared with PS-DOX, Ang-PS-DOX demonstrated significantly higher cellular uptake and stronger cytotoxicity in C6 cells. In vivo pharmacokinetics and brain distribution experiments revealed that Ang-PS-DOX achieved a more extensive distribution and more abundant accumulation in glioma cells than PS-DOX. Moreover, the survival time of glioma-bearing rats treated with Ang-PS-DOX was significantly prolonged compared with those treated with PS-DOX or a solution of free doxorubicin. These results suggested that Ang-PS-DOX can target glioma cells and enhance chemotherapeutic efficacy.

Crystals of e-phase tris(8-hydroxyquinoline) aluminum (e-Alq3) were prepared by using physical vapor deposition (PVD) method in a double zone tube furnace. The structural properties of the e-Alq3 crystals were investigated by using an X-ray single crystal diffractometer (XSCD) and a high resolution scanning electron microscope (SEM). Large straight steps were observed from the side face of the pine needle-like crystals. The straight steps are parallel with each other like terraces and the widths of the steps are fixed, indicating that the e-Alq3 crystals may have layered structures. The photoluminescence (PL) spectra at different temperatures (7 K, 66 K, 220 K, 300 K and 350 K) and the absorption spectrum were also investigated. The optical band gap of the e-Alq3 crystals was calculated to be about 2.82 eV. This value is a little larger than that of amorphous mer-Alq3 (about 2.7 eV), indicating a minimizing of impurities, grain boundaries and defects.