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Objectives: This study aims to investigate the effectiveness of tofacitinib, a Janus kinase (JAK) 1/JAK3 inhibitor, in treating murine lupus, and also explore 12 related genes downstream of JAK-signal transducer and activator of transcription (STAT) signaling pathways to find the underlying mechanism. Materials and methods: This study was conducted between July 2017 and January 2020. Fifty-seven female BALB/c mice (aging 8 to 10 weeks old; weighing 18 to 20 g) were assigned to a saline control (SC) group and a pristane-induced lupus group. The latter included four groups, namely, pristane control (PC), tofacitinib (T), methylprednisolone (MP), and tofacitinib plus methylprednisolone (T+MP). Animal models of lupus were induced with pristane, whereas SC mice were treated with normal saline. From the 22nd week after induction, each group was given the aforementioned corresponding intervention for 11 weeks. The following variables were tested: serum concentrations of anti-double-stranded deoxyribonucleic acid (anti-dsDNA), interleukin 6 (IL-6), and interferon gamma (IFN-γ); number of regulatory T (Treg) cells; messenger ribonucleic acid levels of forkhead box P3 and 12 related genes downstream of JAK-STAT pathway; and renal impairment. Results: Red swollen joints and proteinuria were first observed in PC after the 12th week. After treatment, T, MP, and T+MP showed relieved red swollen joints and splenomegaly, as well as decreased urine protein, anti-dsDNA, IL-6, IFN-γ, Treg cells, pathological scores, and hyperplasia of mesangial matrix in glomeruli compared with PC. The IFN regulatory factor 7 level was higher in T+MP (p0.05) and MP (p>0.05) than in PC after treatment. The expression of suppressor of cytokine signaling (SOCS) 1 was lower in T (p>0.05), T+MP (p0.05) than in PC. The SOCS3 level was higher in T (p>0.05) and T+MP (p0.05) than in PC. Conclusion: Tofacitinib can ameliorate glomerulonephritis and arthritis in a pristane-induced murine model of lupus. SOCS3 gene may be involved in the therapeutic mechanism of tofacitinib.

To meet the ever-increasing demands for high-quality network services, a software defined network (SDN) can support various virtual network functions (VNFs) using virtualization technology. Due to network dynamics, an SDN needs to be updated frequently to optimize various performance objectives, such as load balancing. Most previous solutions first determine a new network configuration (e.g., target VNF placement and flow routing) based on the current workload, and then update the VNF placement and routing paths of the existing flows. However, due to massive VNF's state migration and slow update of the flow table, unacceptable update delay may occur, especially in large or frequently changed networks. In this paper, we address the real-time network update, which jointly considers the optimization of the service function chain (SFC) update and the routing update. We propose the delay-satisfied NFV-enabled network update (DSNU) problem, and prove its NP-Hardness. We design an algorithm with bounded approximation factor to solve this problem. To further reduce the delay, we also design an efficient algorithm for the update scheduling. The experimental results show that our method can reduce the network update delay by about 86% compared with the previous network update methods while preserving a similar network performance, \ie, the VNF instance load ratio increases by less than 5%.

This paper studies an asymptotic solvability problem for linear quadratic (LQ) mean field games with controlled diffusions and indefinite weights for the state and control in the costs. We employ a rescaling approach to derive a low dimensional Riccati ordinary differential equation (ODE) system, which characterizes a necessary and sufficient condition for asymptotic solvability. The rescaling technique is further used for performance estimates, establishing an $O(1/N)$-Nash equilibrium for the obtained decentralized strategies., 32 pages

Large software defined networks use a cluster of distributed controllers to process flow requests from a massive number of switches. To cope with traffic dynamics, this paper studies a new problem of how to improve the residual capacity available at the controllers to handle request bursts experienced at the switches. While the total residual capacity is a constant under a given total capacity of all controllers and a given total workload from all switches, this paper considers the residual capacity available to each individual switch, which depends on how the switches are mapped to the controllers for management. We focus on how to maximize the minimum residual capacity available to any switch . The prior work either provides poor residual capacity or incurs heavy synchronization overhead by simulation results. This paper proposes a new method called indirect multi-mapping that achieves both high residual capacity and low synchronization cost. We formally define a non-linear integer optimization problem for max-min residual capacity under indirect multi-mapping. We then approximate the problem as two sub-problems: switch-controller mapping selection and weight assignment for each switch-controller mapping. We solve these sub-problems and formally analyze their approximate factor. We implement the proposed solution on an SDN testbed for experimental studies and use simulations for large-scale investigation. Our evaluation shows that indirect multi-mapping improves the minimum residual capacity by 49.8% on average and reduces the synchronization cost by 41.9-60.3% on average when compared with the alternatives.

In a software defined network, the controller needs to obtain/collect traffic measurement information ( i.e. , flow statistics) from switches for different applications, such as traffic engineering. Existing solutions seldom consider the per-switch cost, which may lead to heavy statistics collection cost ( e.g. , high CPU overhead) on some switches. Due to limited computing power on most commodity switches, heavy statistics collection cost on those switches may seriously interfere with the basic rule operations, especially when some switches need to deal with many new-arrival flows or update routes of existing flows. To address this challenge, we design and implement efficient flow statistics collection (FSC) with limited interference on the basic rule operations. We formally propose a cooperative flow statistics collection with per-switch cost constraint (CP-FSC) problem. We prove that the CP-FSC problem is NP-hard and present an efficient algorithm with approximation ratio 1/2, based on dynamic programming. To reduce the time complexity, a greedy-based algorithm with approximation ratio 1/3 is also presented. We implement the proposed FSC algorithms on our SDN platform. The experimental results and the extensive simulation results show 36%-59% performance improvement compared with the existing solutions.

Objectives This study aims to evaluate the frequency and clinical and laboratory features of interstitial lung disease (ILD) in Chinese patients with systemic lupus erythematosus (SLE) and to evaluate the association of ILD with the clinical features. Patients and methods The study included 505 SLE patients (64 males, 441 females; mean age 35.3±15.3 years; range, 14 to 87 years) who were categorized into two groups as 449 patients without ILD and 56 patients with ILD based on evidence obtained from high-resolution computed tomography images. The demographic data, clinical and laboratory findings, SLE disease activity index score, and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index of all patients were also recorded and statistically analyzed. Results The ILD frequency in patients with SLE was 11.1%. Compared to the group of SLE patients without ILD, the group of SLE patients with ILD possessed the following statistical differences: elderly age, longer illness duration, lower level of anti-double-stranded deoxyribonucleic acid, and higher level of serum complement 3, increased ratios of Raynaud's phenomenon, moist rales and tachypnea. Multivariate logistic regression results suggested that elderly age (≥60 years), long illness duration (1-10 years, ≥10 years), Raynaud's phenomenon, and tachypnea were statistically associated with the occurrence of ILD in SLE patients. Conclusion Chinese SLE patients who possessed the factors that were statistically associated with ILD, namely, elderly age (≥60 years old), long illness duration (≥1 years), Raynaud's phenomenon, and tachypnea, were recommended to be monitored for the possibility of ILD.

We study mean field Stackelberg games between a major player (the leader) and a large population of minor players (the followers). By treating the mean field as part of the dynamics of the major player and a representative minor player, we Markovianize the decision problems and employ dynamic programming to determine the equilibrium strategy in a state feedback form. We show that for linear quadratic (LQ) models, the feedback equilibrium strategy is time consistent. We further give the explicit solution in a discrete-time LQ model.

Network Function Virtualization (NFV) is a new paradigm to enable service innovation through virtualizing traditional network functions. To construct a new NFV-enabled network, there are two critical requirements: minimizing server deployment cost and satisfying switch resource constraints . However, prior work mostly focuses on the server deployment cost, while ignoring the switch resource constraints ( e.g. , switch’s flow-table size). It thus results in a large number of rules on switches and leads to massive control overhead. To address this challenge, we propose an incremental server deployment (INSD) problem for construction of scalable NFV-enabled networks. We prove that the INSD problem is NP-Hard, and there is no polynomial-time algorithm with approximation ratio of $(1-\epsilon) \cdot \ln m$ , where $\epsilon $ is an arbitrarily small value and $m$ is the number of requests in the network. We then present an efficient algorithm with an approximation ratio of $2\cdot H(q\cdot p)$ , where $q$ is the number of VNF’s categories and $p$ is the maximum number of requests through a switch. We evaluate the performance of our algorithm with experiments on physical platform (Pica8), Open vSwitches, and large-scale simulations. Both experimental results and simulation results show high scalability of the proposed algorithm. For example, our solution can reduce the control and rule overhead by about 88% with about 5% additional server deployment, compared with the existing solutions.

Network Function Virtualization (NFV) is a rapidly developing network architecture concept, in which virtualization technologies transform network functions in hardware devices to software middleboxes. For reasons such as improving security and performance, flows in the network need to traverse specific service function chains (SFCs). Due to the rapid increases in traffic volume, traffic variety, and service requirements, it becomes much complex for SFC routing. The existing solutions for joint middlebox placement and routing still consume a lot of forwarding rules and result in overloaded controllers, which decrease the scalability of middlebox networks. To solve these problems, this paper proposes a joint deployment scheme, which uses the consolidated middlebox to simplify the processing of SFC and uses the virtual switch (e.g., OVS) to reduce TCAM usage. Specifically, We formulate the joint optimization of consolidated middleboxes and the virtual switch placement, as well as routing (JPR) problem into an integer linear programming model, and prove its NP-hardness. An efficient algorithm is proposed to solve the JPR problem. Extensive simulation results show that the proposed solution can achieve better load balancing while using fewer forwarding rules than other existing algorithms. For example, our algorithm can reduce the maximum flow entries by 69%, and reduce the maximum link load by 45% compared with the state-of-the-art approaches.

Anycast mechanism has been used as a fundamental technology in many fields, with multiple servers providing the same service. Each request does not care which server it is served by. For security and performance reasons, requests must meet the requirements of service function chain (SFC) in network function virtualization (NFV) enabled networks. Though the routing of SFC has been widely studied, most of these works focus on unicast, which does not involve server selection, and cannot be applied directly for anycast. If we simply combine the traditional anycast algorithms and SFC unicast routing algorithms, it will overload the links and servers. Since overloaded links and servers will reduce the quality of services, it is important to balance the load of links and servers. In this work, we focus on designing an SFC routing mechanism for anycast that takes server selection into account and achieves load balancing among servers as well as links with the help of software defined network (SDN). We first propose the problem of joint server selection and SFC routing for anycast in NFV-enabled SDNs (JSR). Then based on the method of random rounding, we design an algorithm called RBLB with approximate ratio guarantee that can solve the JSR problem. The extensive simulation results show that our algorithm can reduce the load of servers and links. For example, algorithm RBLB can reduce the server load by 41.4%–60.1% compared with the comparison algorithm, when the number of requests exceeds 20k.

White light-emitting diodes (WLEDs), which have high luminous brightness, longevity, low energy consumption and friendliness of environment, could be employed in diverse fields. Nevertheless, commercial phosphors are short of red light component. New phosphors which can emit red light are required. Mn2+ doped aluminum nitride (marked as AlN) red phosphors were prepared by a simple solid-state reaction. X-ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS), as well as photoluminescence (PL) spectra are utilized to characterize the prepared samples. The preparing process of AlN phosphors, phase formation and crystal structure, morphology, and photoluminescence are detailedly investigated. For Mn2+ doped AlN phosphor(marked as AlN:Mn2+), it exhibits an intense red emission caused by the 4T1(4G)-6A1(6S) transition of Mn2+. The unusual red emission of Mn2+ is ascribed to the strong nephelauxetic and crystal field between Mn2+ and the tetrahedrally coordinated N3−. The oxygen-related defects in AlN have a great influence on the photoluminescence properties of the Mn2+ doped AlN. The AlN:Mn2+ phosphors exhibits a high brightness, high color purity, and lower saturation, which make it a great candidate of red phosphors for white light-emitting diodes (WLEDs).

The (Fe1-xDyx)3C@C composites were produced by a simple sol-gel route. The structure, composition, morphology and magnetism of the composites are studied by many characterization methods, for example, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning and transmission electron microscopy (SEM, TEM) as well as vibrating sample magnetometer (VSM). Analysis of the above results indicates that the (Fe1-xDyx)3C is embedded in carbon nanotubes and carbon matrix and displays ferromagnetic properties. Moreover, this indicates that saturation magnetization (MS) values of the composites tend to increase with the increase in Dy doping. More importantly, we investigates the electrochemical hydrogen production capacity of the (Fe1-xDyx)3C@C composites.

Software defined networking is a new paradigm that separates the control plane from the data plane. To provide high scalability and reduce the controller load in a large-scale software defined network (SDN), a natural way is to deploy a cluster of distributed controllers so as to cooperatively manage the network. However, since each controller just manages a set of the connected (or associated) switches and usually holds the information of these switches (and connected links), it may result in controller load imbalance and link load imbalance. Thus, both controller load and link load should be optimized to achieve better QoS in SDNs. To this end, this paper tries to answer the following question: how to perform both controller load balancing and link load balancing in an SDN? We formulate the load-balancing routing for both links and controllers (LBR-LC) problem in an SDN, and prove its NP-hardness. A rounding-based algorithm is proposed to solve this problem, and the approximation performance is also analyzed. Moreover, we discuss the efficient mechanism for network status maintenance among distributed controllers. The extensive simulation results show that our proposed algorithm can reduce the maximum controller response time by 70% compared with the previous solution, while only increasing the maximum link load by 3%.

(Fe1−xNdx)3N was successfully prepared by a simple complex method. The as-synthetized (Fe1−xNdx)3N exhibits regular rod-like morphology and excellent magnetic properties. X-ray diffraction, scanning electron microscopy with Energy dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, as well as vibrating sample magnetometer are employed to analyze the structure, morphology and magnetic properties of the samples. What’s more, when the Nd doping concentration is 3%, the coercivity reaches a higher value of 664.61 Oe. It is much higher than the coercivity of 408.84 Oe for the pure Fe3N. The material shows a trend of transition to hard magnet. It opens the way for other soft magnet translating into hard magnet by doping rare earth ions.

To better serve a diversity of flows, load balancing is crucial to ensure operational efficiency. However, previous works for load balancing have several disadvantages: 1) limited applicability with sub-flow scheduling (e.g., LetFlow); 2) hash collision (e.g., ECMP); or 3) transient network congestion due to reactive scheduling for traffic dynamics (e.g., Hedera and DevoFlow). An important reason for the above disadvantages is that it is difficult to provide fully fine-grained flow control for load balancing in an SDN as the flow table size of each SDN switch is usually limited. Inspired by the fact that a virtual switch (vswitch) has more powerful processing capacity and more flow entries compared with a physical switch, the previous work (e.g., Presto) deploys one vswitch for each ingress switch, and achieves the load balancing through efficient flow routing. However, this mechanism may lead to high cost and not well deal with topology asymmetry. Thus, this paper proposes to achieve the load balancing by incrementally deploying a certain number of vswitches in an SDN. We formulate the joint optimization of vswitch deployment and routing (JVR) problem as an integer linear program, and prove its NP-hardness. A rounding-based algorithm with bounded approximation factors is proposed to solve the JVR problem. We implement the proposed algorithm on an SDN testbed for experimental studies and use simulations for large-scale investigation. The experimental results and simulation results show high efficiency of our algorithm. For example, our proposed algorithm can reduce the link load ratio by about 41.5% compared with ECMP by deploying a small number of virtual switches.

A series of Mg-Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine. The structure and surface properties of Mg-Al oxides are modulated by changing the Mg/Al ratios, calcination temperature and treatment with probe molecules. Detailed characterization, including X-ray diffraction, 27Al magic angle spinning nuclear magnetic resonance spectroscopy, N2-adsorption, NH3-temperature-programmed desorption, CO2-temperature-programmed desorption and X-ray photoelectron spectroscopy are carried out to determine the physicochemical properties of these catalysts. The Mg-Al oxides with Mg/Al = 3 exhibit the highest activity in the reaction, which possess a large number of surface weak basic sites and a relatively small number of weak acidic sites. The role of the acidic and basic sites in the reaction process is systematically investigated, and are shown to serve as adsorption and activation sites for amines and alcohols, respectively. Under the synergistic effect of these acid-base centers, the oxidative coupling process successfully occurs on the surface of Mg-Al mixed oxides. Compared with the acidic sites, the weak basic sites play a more important role in the catalytic process. The acidic sites are the catalytic centers for the benzyl alcohol activation, which control the reaction rate of the oxidative coupling reaction.

We investigated the CT process between a 4-mercaptobenzoic acid (4-MBA) monolayer and TiO2 NPs under high pressure using surface-enhanced Raman scattering (SERS). Employing the CT enhancement mechanism of semiconductors, we explore the CT process and explain how the pressure affects the process in the 4-MBA@TiO2 system.

Flow routing is one of the most important issues in a software defined network (SDN), and faces various challenges. For example, each link may not be reliable all the time (or with a failure probability), and the flow-table size on each switch is limited. Existing solutions about reliable flow routing may result in a longer failure recovery delay, a large number of flow entries or massive control overhead. To this end, we propose to achieve throughput optimization with the constraint that the forwarding reliability probability of each switch pair should exceed a threshold (e.g., 99.9%). We formally define the reliable flow routing (RLFR) problem with flow-table size constraint. We present a rounding-based algorithm and analyze its approximation performance. We further extend our algorithm to preserve the throughput of each switch pair even with link failures. We implement our proposed algorithms on the SDN platform. The experimental results and large-scale network simulation results show that our algorithms can improve the network throughput by about 48.0% and reduce the maximum number of required flow entries by about 53.1%, compared with the existing solutions under the reliability requirement.

Link failure is a major problem that must be addressed, which occurs frequently in large networks. In a software-defined network, the recovery scheme for single link failure can be divided into two categories: proactive and reactive. For reactive scheme, it takes a long time to recover due to the controller participation. Though the proactive scheme can achieve faster recovery, it may consume a large number of forwarding rules, which is typically limited on switches due to expensiveness and power hungry. Therefore, this paper proposes a proactive recovery scheme for single link failure based on segment routing with less forwarding rules. In the proposed scheme, we regard the affected flows through the same link as an aggregated flow and use the link protection methods to achieve link failures recovery. The link protection methods calculate backup paths for each link of the working path, so we propose the backup paths calculation problem and formulate it as an mixed integer non-linear programming model. To solve the problem and avoid link congestion, we design an efficient algorithm to select the most appropriate backup path. In addition, due to the limitation of the maximal number of MPLS labels that the packet header can hold, we design an algorithm to divide the working and backup path into segments to meet the hardware requirements. The simulation results show that the proposed algorithms outperform CAFFE and SPR by 14.7% and 77.1% on recovery time, and outperform CAFFE by 21.5% on forwarding rules consumption. Moreover, the proposed scheme does not cause congestion in post-recovery network.

MgFe2O4 with inverse spinel structure is demonstrated to be an efficient support for constructing practical potential Pt catalyst (Pt/MgFe2O4). The resultant Pt/MgFe2O4 exhibits excellent catalytic behavior in CO oxidation under normal temperature and humidity. TOF calculated based on the content of Pt is 0.131 s–1. The excellent performance of Pt/MgFe2O4 attributes to the presence of surface undercoordinated lattice oxygens on MgFe2O4 support. These oxygens could participate in the initial CO oxidation and then be recovered under O2 conditions. Over this Pt/MgFe2O4 catalyst, CO catalytic oxidation should mainly follow a redox mechanism.

Hollow Gd 2 O 3 :Eu 3+ (denoted as H-Gd 2 O 3 :Eu 3+ ) nanospheres with excellent magnetic and luminescence properties were prepared through a self-template method using Gd(OH)CO 3 :Eu as template to form hollow precursors. The size of Gd 2 O 3 :Eu 3+ shell is 20 nm for H-Gd 2 O 3 :Eu 3+ nanospheres annealed at 600 °C with particle diameter of 200 nm. The hollow structure improved the luminescent intensity in contrast to solid spheres. The systematic studies about the effect of calcination temperature on the luminescence and magnetic properties were reported. Luminescent spectra shows that the I 610/590 (asymmetry factor of luminescence) varies with the calcination temperature, indicating that the color purity and local environment of Eu 3+ in Gd 2 O 3 changes. Moreover, the magnetization (M) becomes stronger while increasing the calcination temperature. The H-Gd 2 O 3 :Eu 3+ nanospheres may have potential application in magnetic resonance image (MRI), drug delivery, and drug loading and release.

We investigated the CT process between a 4-mercaptobenzoic acid (4-MBA) monolayer and TiO2 NPs under high pressure using surface-enhanced Raman scattering (SERS). Employing the CT enhancement mechanism of semiconductors, we explore the CT process and explain how the pressure affects the process in the 4-MBA@TiO2 system.

Fe3C is a promising material with both high saturation magnetization and chemical stability. In this article, we present a facile sol–gel route for the synthesis of Fe3C/Fe nanocomposites, in which bromide was found to be the inducing agent for the conversion of FeCl3 to Fe3C. X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer were used to characterize the composites. The experimental results show that the composition and magnetic properties of Fe3C/Fe composites can be controlled by changing reaction temperatures, reaction time and the amount of inducing agent. Moreover, the possible formation mechanism of as-prepared nanostructures is discussed.

A method for the investigation of photocatalytic degradation of organic molecules adsorbed on the surface of a compound nanostructure, silver nanoparticle (Ag NP) modified titania nanotubes (TiO 2 NTs), namely Ag/TiO 2 NTs, was proposed. The method was applied to the photocatalytic degradation of rhodamine 6G (R6G) dye molecules in order to determine its effectiveness. The surface-enhanced Raman scattering (SERS) technique was employed to monitor the photodegradation processes on these bifunctional nanostructures. The photocatalytic characteristic was attributed to the TiO 2 NTs; however, the SERS activity was caused by the Ag NPs. The Ag/TiO 2 NTs were able to detect R6G molecular probes with concentration down to 10 −8 M. The substrates could not only degrade the adsorbates, but also discard them off under ultraviolet irradiation owing to the high photocatalytic activity of TiO 2 . Thus, the substrates were able to self-clean and be reused for a new SERS detection cycle. The photodegradation and SERS results revealed that Ag/TiO 2 NTs acted as promising candidates for photocatalytic activity and SERS substrates; and exhibited high recyclability in the detection of organic molecules. The optimized SERS-active substrates were then employed to study the photodegradation of R6G. The photodegradation kinetics analysis was assessed by selecting the strongest SERS peaks which indicated that the kinetics of the photodegradation of R6G followed the pseudo-first order reaction. Finally, the results presented herein demonstrated that the fabricated Ag/TiO 2 NTs nanostructures were remarkably suitable as photocatalytically active SERS substrates. Further, the substrates could be effectively utilized for highly sensitive in situ monitoring of the surface photodegradation processes of organic molecules and could be recycled in a more environmentally sustainable manner.

The synthetic strategy for the creation of Double-shell structure is based on a facile calcining process, in which carbon middle layer of Fe 3 O 4 @C@Y 2 O 3 :Eu 3+ @C@Y 2 O 3 :Eu 3+ composite nanostructures was calcined away. We obtained the Fe 3 O 4 @Y 2 O 3 :Eu 3+ @Y 2 O 3 :Eu 3+ nanocomposites with luminescent and magnetic properties. X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and photoluminescence spectroscopy (PL) were used to analyze the structure, morphology, magnetic and luminescence properties of the composites. The nanocomposites has spherical morphology with narrow size distribution. In addition, they exhibit good magnetization with the saturation magnetization of 1.99 emu/g) and unique red emission for Eu 3+ at 610 nm.

The photoexcited electron transfer rate represents one of the most important properties required for photovoltaic devices. However, the fabrication of solar cells with a faster electron transfer remains a technological challenge. Regulating the energy level alignment of acceptor-donor system by the incorporation of foreign ions is one of the most promising strategies to achieve this aim. Herein we demonstrate that the incorporation of silver ions into TiO2 nanocrystals results in a remarkable reduction of energy offset between the conduction band edge of acceptor and the lowest unoccupied molecular orbital of donor. In particular, the electron transfer life time was shortened from 30.2 to 18.3 ps, i.e., almost 40% faster than pure TiO2 acceptor, thus leading to a notable enhancement of power conversion efficiency by almost 38% in organic/inorganic hybrid solar cells. The reduction of the ‘excess’ energy offset accelerates the electron transfer, which is expected to have an important role in applications of solar energy conversion and photon detectors.

In this paper, co-precipitation synthesized Fe 3 O 4 microspheres have been encapsulated with nonporous silica and further functionalized by the deposition of Y 2 O 3 :Eu 3+ phosphors through a simple co-precipitation process, realizing a hollow structured material with mesoporous, magnetic and luminescent properties. The results reveal that the material shows typical ordered mesoporous characteristics, and have monodisperse spherical morphology with smooth surface and narrow size distribution. Additionally, the multifunctional nanocomposite shows the characteristic emission of Eu 3+ ( 5 D 0 – 7 F 1–4 ). Magnetism measurement reveals the paramagnetic feature of the samples. Furthermore, we also compared the magnetic and fluorescent properties of solid Fe 3 O 4 @SiO 2 @Y 2 O 3 :Eu 3+ and Fe 3 O 4 @HM-SiO 2 @Y 2 O 3 :Eu 3+ .

In this study, the bifunctional Fe@C@Gd 2 O 3 :Eu 3+ composites were prepared via a simple co-precipitation progress followed by a subsequent heat treatment under N 2 atmosphere. The reactive carbon interlayer offers many advantages including separating photoluminescent material from magnetic material and reducing magnetite Fe 3 O 4 to metal Fe. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM) and photoluminescence spectroscopy (PL) were used to analyze the structure, morphology, magnetic and luminescence properties of the composites. The Fe@C@Gd 2 O 3 :Eu 3+ composites with well-crystallized and core–shell structure were prepared and displayed good ferrimagnetic behavior at room temperature and a strong red emission. In addition, due to the excellent magnetic and luminescence properties of the prepared composites, they may have many great potential applications in many fields, such as biological imaging, cell tracking and drug delivery.

Multifunctional Fe@C@Y2O3:Eu3+ nanocomposites were prepared by the solvo thermal method, and their structure, magnetic and luminescent properties were characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and scanning electron microscope (SEM). Results show that the nanocomposites are spherical with a mean diameter of 700 nm and there are high special saturation magnetization (47.4 emu/g) and strong red emission under UV-light. Even dispersed in water solution, the nanocomposites also exhibit a strong red emission under ultraviolet light radiation, and it could be manipulated using an external magnet. Thus it looks promising for application in biomedicine field, especially in drug targeting and fluorescence label. And we also discussed the effect of the electron transfer process between the Fe magnetic core and Y2O3:Eu3+ shell.

GdAl3(BO3)4:Ln3+ (Ln3+:Eu3+, Tb3+, Dy3+) nano-phosphors were prepared by sol–gel method. The structure properties of the phosphors are characterized by XRD, and GdAl3(BO3)4:Ln3+ nano-phosphors have average sizes around 40 nm. The doping concentrations of Eu3+, Tb3+ and Dy3+ ions in GdAl3(BO3)4 nano-phosphors are from 1 to 9 mol% for Eu3+ ions, from 2 to 12 mol% for Tb3+ ions and from 1 to 5 mol% for Dy3+ ions, respectively. The luminescent properties of rare-earth ions doped GdAl3(BO3)4 nano-phosphors are analyzed by the photoluminescence spectra, which prime doping concentration of Eu3+, Tb3+, and Dy3+ ions are at 5, 12 and 3 mol%, respectively. The energy transfers in the luminescent processes of rare-earth ions doped GdAl3(BO3)4 nano-phosphors are discussed.

In this paper, we report on the bifunctional Fe 3 O 4 @SiO 2 @YP 0.1 V 0.9 O 4 :Dy 3+ nanocomposites were prepared by the solvothermal method and sol–gel method. The structure, photoluminescence (PL) and magnetic properties of the nanocomposites were characterized by means of X-ray diffraction, scanning electron microscope, transmission electron microscope, PL excitation and emission spectra and vibration sample magnetometry. It is shown that Fe 3 O 4 @SiO 2 @YP 0.1 V 0.9 O 4 :Dy 3+ nanocomposites with a core–shell structure present excellent fluorescent and magnetic properties. Additionally, the effects of the magnetic field on the luminescence properties of nanocomposites were discussed.

Multifunctional nanocomposites with Fe/Fe3O4 nanoparticles as the core and europium-doped yttrium oxide (Y2O3:Eu) as the shell (Fe/Fe3O4@Y2O3:Eu) have been obtained successfully employing a solvothermal method. The nanocomposites showed both ferrimagnetic behavior and unique europium fluorescence properties with high emission intensity. The spectra changes induced by the UV light irradiation and the magnetic field have been systematically studied and compared in detail. The relationship between fluorescence and magnetic properties of the multifunctional nanocomposites has been investigated in our manuscript. These multifunctional nanocomposites could be used in a number of biomedical applications, such as drug targeting, cell separation and bioimaging.

The multifunctional Fe3O4@Y2O3:Eu3+ nanocomposites were prepared by a facile solvothermal method with Fe3O4 nanoparticles as the core and europium-doped yttrium oxide (Y2O3:Eu3+) as the shell. It is shown that Fe3O4@Y2O3:Eu3+ nanocomposites have a strong photoluminescence and special saturation magnetization Ms of 6.1 emu/g at room temperature. The effects of the magnetic field on the luminescence intensities of the nanocomposites are being discussed. The multifunctional nanocomposites with magnetic resonance response and fluorescence probe properties may be useful in biomedical applications, such as cell separation and bioimaging.

Multifunctional Fe/Fe3O4@ZnS nanocomposites were synthesized by hydrothermal method, with Fe/Fe3O4 doped Co ion as the magnetic core and ZnS as the luminescent shell. The morphology, structure, luminescent and magnetic properties of the nanocomposites were investigated by XRD, FESEM, photoluminescence PL and VSM. The maximum emission peak and special saturation magnetization Ms of the nanocomposites are at 467 nm and 78.6 emu/g, respectively. For the nanocomposites, it is shown that there are both better magnetic behavior and fluorescence properties.

In this study, the hydrothermal synthesized Fe3O4 nanoparticles are encapsulated with SiO2 via the Stober method and further functionalized by the deposition of YVO4:Eu3+ phosphors, realizing a hybrid material with magnetic and luminescent properties. The bifunctional nanocomposites displayed a strong red emission and good ferrimagnetic behavior at room temperature. The high magnetization values make the nanocomposites quickly respond to the external magnetic field. The results also indicate that the nanocomposites may have potential applications for optical imaging or drug delivery. Moreover, we discussed the effects of the magnetic field on the luminescence intensity.

Fe–Co alloy and Sm3+-substituted magnetite nanowire composites (CoxFe1−x/CoyFe1−ySmzFe2−zO4) have been synthesized via a hydrothermal method without using surfactants or templates. The effects of substitution on structure and morphology were investigated by powder X-ray diffraction, X-ray photoelectron spectroscopy, Mossbauer spectroscopy, and transmission electron microscopy (TEM). The TEM image shows that the average diameter of the magnetite nanowires is about 40 nm and the length is several micrometers. The z=0.1 composite shows relatively high saturation magnetization (92.3 emu/g) detected by a vibrating sample magnetometer. The possible growth mechanism of the nanowires is discussed on the basis of the crystal structure of the materials. From the perspective of thermodynamics, we explain the postulated mechanism of the hydrothermal reaction.

A series of iron–cobalt alloy and cobalt–ferrite composites doped with La3+ (CoxFe1−x/CoyLazFe3−y−zO4) in which the Fe–Co alloy has either a bcc or a fcc structure and the oxide is a spinel phase, have been synthesized by using the disproportionation of Fe (OH)2 and the reduction of Co (II) by Fe0 in a concentrated and hot KOH solution. when x ≤ 0.1, the structures of the FexCo1−x alloy and cobalt–ferrite are fcc structure; and when x ≥ 0.25, the structures of the FexCo1−x alloy is bcc structure. The fcc structure of alloy is favored for [KOH] close to 9 N, Co(II)/Fe(II) ratios between 0.5 and 0.9 and short reaction time of synthesis. And the bcc structure of the alloy is favored for [KOH] close to 1 N, Co(II)/Fe(II) ratios between 0.1 and 0.5 and long reaction time of synthesis. A low [KOH] favors nucleation leading to octahedral of 1 µm. And [KOH] of 9–12 N favors particle growth. The metal occurs in square particles of 100–150 nm included within the spinel. Powder X-ray diffraction (XRD), thermal gravity analysis (TGA) and different thermal analysis (DTA), scanning electron microscope (SEM), transmission electron micrograph (TEM) and vibrating sample magnetometer (VSM) were employed characterize the crystallite sizes, structure, morphology and magnetic properties of the composites. And the effect of the Co(II)/Fe (II) ratio (0 ≤ Co/Fe ≤ 1), concentration of KOH, reaction time and substitution Fe3+ ions by La3+ ions on structure, magnetic properties of the composites were investigated.