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The development of a sensing platform with high sensitivity and specificity, especially programmability and universal applicability, for the detection of clinically relevant molecules is highly valuable for disease monitoring and confirmation but remains a challenge. Here, for the first time, we introduce the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system into an immobilization-free electrochemical biosensing platform for sensitively and specifically detecting the disease-related nucleic acids and small molecules. In this strategy, a modular rolling circle amplification (RCA) is designed to transform and amplify the target recognition event into the universal trigger DNA strand that is used as the trigger to activate the deoxyribonuclease activity of CRISPR/Cas12a for further signal amplification. The cleavage of the target-activated blocker probe allows the methylene blue-labeled reporter probes to be captured by the reduced graphene oxide-modified electrode, leading to an obviously increased electrochemical signal. We only need to simply tune the sequence for target recognition in RCA components, and this strategy can be flexibly applied to the highly sensitive and specific detection of microRNAs, Parvovirus B19 DNA, and adenosine-5'-triphosphate and the calculated limit of detection is 0.83 aM, 0.52 aM, and 0.46 pM, respectively. In addition, we construct DNA logic circuits (YES, NOT, OR, AND) of DNA inputs to experimentally demonstrate the modularity and programmability of the stimuli-responsive RCA-CRISPR/Cas12a system. This work broadens the application of the CRISPR/Cas12a system to the immobilization-free electrochemical biosensing platform and provides a new thinking for developing a robust tool for clinical diagnosis.

Development of selective and sensitive methods for on-site assay of tetracycline (TC) is of great significance for public health and food safety. Herein, a valid ratiometric fluorescence strategy using g-C3N4 nanosheets coupled with Eu3+ is designed for the assay of TC. In this strategy, both Eu3+ and g-C3N4 nanosheets serve as the recognition units of TC. The blue fluorescence of g-C3N4 nanosheets can be quenched by TC via the inner filter effect (IFE); meanwhile, the red fluorescence of Eu3+ can be enhanced by TC through the antenna effect (AE). The synergistic effect of AE and IFE caused by TC makes the developed ratiometric fluorescent sensor display a wide linear range for TC from 0.25 to 80 μM with a detection limit of 6.5 nM and a significant fluorescence color evolution from blue to red. Given its simplicity, free-label, excellent selectivity, high sensitivity, and recognizable color change, point-of-care testing systems, including smartphones and test paper-based assays, are developed for the visual sensing of TC. The integration of smartphones and test paper on a ratiometric fluorescent sensor greatly reduces the detection cost and time, providing a promising method for the qualitative discernment and semi-quantitative assay of TC on-site. Moreover, the potential application of the approach is also verified by detecting TC in milk.

The efficacy of susceptible variants derived from genome-wide association studies (GWAs) optimizing discriminatory accuracy of colorectal cancer (CRC) in Chinese remains unclear. In the present validation study, we assessed 75 recently identified variants from GWAs. A risk predictive model combining 19 variants using the least absolute shrinkage and selection operator (LASSO) statistics offered certain clinical advantages. This model demonstrated an area under the receiver operating characteristic (AUC) of 0.61 during training analysis and yielded robust AUCs from 0.59 to 0.61 during validation analysis in three independent centers. The individuals carrying the highest quartile of risk score revealed over 2-fold risks of CRC (ranging from 2.12 to 2.90) compared with those who presented the lowest quartile of risk score. This genetic model offered the possibility of partitioning risk within the average risk population, which might serve as a first step toward developing individualized CRC prevention strategies in China.

Herein, an innovative photocathodic enzymatic biosensor is proposed with poly {4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]-benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophene-4,6-diyl} (PTB7–Th) as donor–acceptor–type photoactive material and three–dimensional (3D) polyaniline hydrogels (PAniHs) as both electron transfer layer and biomolecule carrier. Based on the enhancement effect of PAniHs on the charge separation and electron transfer of PTB7–Th and the competitive consumption of dissolved oxygen (O2) between the xanthine oxidase (XOD)–guanine catalytic reaction and O2–sensitive PTB7–Th/PAniHs, the proposed photocathodic enzymatic biosensor has been demonstrated to detect guanine with the advantages of low limit of detection (0.02 μM), wide linear range (from 0.1 to 80 μM), simple and convenient preparation process, satisfactory stability, and photochemical signal amplification independent of any exogenous electron donor/acceptor or sensitizer. Remarkably, the proposed photocathodic enzymatic biosensor can not only be extended to other aerobic enzymatic bioanalyses, but also pave a horizon for the application of environmentally friendly conductive hydrogel materials in photoelectrochemical bioanalysis.

Herein, for the first time, we engineered click chemistry reaction to trigger a 3D DNA walking machine for ultrasensitive electrochemical detection of copper ion (Cu2+), which provided a convenient access to overcome the shortcomings of poor selectivity and limited amplification efficiency in traditional determination of Cu2+. Click chemistry reaction drove azido-S2 to bind with alkynyl-S1 for the formation of a walker probe on aminated magnetic polystyrene microsphere@gold nanoparticles (PSC@Au), which opened the hairpin-locked DNAzyme. In the presence of magnesium ion (Mg2+), the unlocked DNAzyme was activated to cleave the self-strand at the facing ribonucleotide site, accompanied by the release of product DNA (S3) and the walker probe. Therefore, the walker probe was able to open the adjacent hairpin-locked DNAzyme strand and then be released by DNAzyme cleavage along the PSC@Au-DNAzyme track. Eventually, the liberated single-strand S3 induced catalytic hairpin assembly (CHA) recycling, resulting in t...

Herein a rigid three-dimensional (3D) DNA "nanosafe-box" (DNB) for encapsulation and release of a recognition probe (N3) is designed to construct an electrochemical biosensor with the use of electroactive two-dimensional metal-organic framework (2D MOF) nanosheets as signal tags for ultrasensitive detection of mercury ion (Hg2+). Initially, N3 is locked in the 3D cavity of DNB by blocker DNA. After addition of target Hg2+, exonuclease III (Exo-III) digestion is initiated to the liberate DNA "key" (K); thereby, the free K triggers a strand displacement reaction for exposing the prelocked N3 to successfully ligate dibenzocyclooctyne (DBCO)-tagged anchor via metal-catalyst-free click chemistry, in which amounts of 2D MOF nanosheets containing Co(II) as electron mediator are introduced accompanied by significant electrochemical response. Compared with traditional linear or stem-loop DNA nanostructure, the well-designed 3D DNB possesses remarkably enhanced mechanical rigidity and structural stability, resulting in improved accessibility of probes and increased loading amounts of signal tags. More importantly, by this way of encapsulation and release of recognition probes, the background signal is decreased dramatically, leading to increased sensitivity of the proposed biosensor. Consequently, this electrochemical biosensor exhibits outstanding analytical performance for Hg2+ detection with a low detection limit of 33 fM and dynamic linear range of 0.1 pM to 10 nM. This strategy offers an ingenious method for detection of metal ions and biomarkers, possessing potential applications in environmental tests and clinical diagnosis.

In this work, on the basis of a new 2D DNA nanoprobe (DNP) and an enzyme-free-target-recycling amplification, an electrochemical biosensor is developed for the ultrasensitive detection of microRNA-21 (miRNA-21). Herein, two ferrocene-labeled bipedal DNPs, which show small steric hindrance and strong stability, are prepared on the basis of the mechanism of the proximity-ligation assay (PLA), improving the space utilization. In the presence of the target, miRNA-21, and a hairpin DNA strand, the DNP will collapse, and then two ferrocene-labeled DNA strands and the miRNA-21 will be simultaneously released from the electrode surface through toehold-mediated strand-displacement reactions (TSDRs), leading to a decrease in the electrochemical signal and realization of enzyme-free target recycling. As a result, the one input target, miRNA-21, could release 2 N ferrocene-labeled DNA strands, achieving a dramatic decrease in the electrochemical signal. Combining DNPs and enzyme-free target recycling, this proposed biosensor showed a linear dependence with miRNA-21 concentration, ranging from 1.0 fM to 10 nM with a detection limit of 0.31 fM. In addition, it is worth mentioning that this biosensor can be regenerated through incubating with three assistant-DNA strands, realizing the reuse of raw materials. Surprisingly, the elaborated biosensor provides a novel strategy for building controllable DNA nanoprobes for the sensitive detection of various biomarkers.

The East Kunlun Orogen in the Northern Qinghai–Tibet Plateau is an ideal region in which to investigate net crustal growth through a process of syn-collisional felsic magmatism. In this paper, we report zircon U–Pb geochronology, whole-rock geochemistry, and multiple isotope data from the Nan’getan quartz diorite porphyrites and syenogranites in the East Kunlun Orogen. Zircon U–Pb ages indicate that the quartz diorite porphyrites and syenogranites were synchronously emplaced at ∼240 Ma. The syenogranites are characterized by a high SiO2 (77.4–79.2 wt%) and differentiation index (DI = 95), and marked depletion in Sr, Ba and Eu, thereby indicating that they are highly fractionated I-type granitoids. These rocks yielded zircon eHf(t) of −4.8 to +3.0 and Hf crustal model ages ( T DM c -Hf) of 1565–1075 Ma. The quartz diorite porphyrites are characterized by a high MgO of 4.19–6.37 wt% and Mg# of 59–61. These porphyrites have varying whole-rock eNd(t) (−13.2 to −10.8), (206Pb/204Pb) 240Ma of 18.325–18.511, (207Pb/204Pb)240Ma of 15.608–15.630, (208Pb/204Pb)240Ma of 38.167–38.614, and δ18OSMOW of 12.5‰–13.7‰. These signatures indicate that the Nan’getan syenogranites were most likely generated by an extensive differentiation of mixed parental magmas with both mantle-derived melt and crustal melt triggered by intrusion or underplating by mantle-derived basaltic magma. The Nan’getan Mg-rich diorites were likely derived from magma mixing between melts of ancient lower crustal materials and melts of an enriched mantle source that was metasomatized by fluids during ascent. In combination with the presence of the regional angular unconformity and the contemporaneous collisional metamorphism, the ∼240 Ma magmatism in the East Kunlun Orogen is inferred to have occurred in a compressional setting from subduction to syn-collision. The Nan’getan granitoids may have recorded the onset of collision between the Bayan Har–Songpan Ganze and East Kunlun terrane and net continental crust growth at ∼240 Ma.

Herein, we construct an ingenious spatially localized amplification reaction (SLAR) by colocalizing the entropy-driven reaction (EDR) in a nanometer space, which greatly accelerates target conversion and realizes the sensitive detection of microRNA-21 (miRNA-21). A large number of EDR complex are hybridized with the prefabricated DNA scaffold via a DNA self-assembly strategy to form the SLAR nanoprobe. Target miRNA-21 triggers interval EDR along the long DNA scaffold, resulting in fluorescence recovery with high signal gain because of the fast release of reporter. Compared with reactions with diffusible components, spatial arrangement of all components of EDR on a nanoscale scaffold can increase the local concentration of reactants, accelerating the interaction between adjacent components, and can also avoid the influence of stochastic diffusion to reduce the unintentional binding interaction between further separated components. Therefore, this SLAR assay displayed an excellent analytical performance for miRNA-21 detection with a detection limit of 6 pM and showed good specificity in distinguishing miRNA-21 from similar miRNAs. In addition, the proposed assay has been experimentally demonstrated for estimation of miRNA-21 in MCF-7 and HeLa cells lysates, which exhibited great promise in the sensitive detection of biomarkers in early diagnosis.

DNAzyme and G-quadruplex are purposed as universal recognition elements to achieve multi-functional signal amplification and readout, showing great potential in the design of biosensors and nanodevices. Herein, the single-stranded DNA (ssDNA) opens the dumbbell-shaped hairpin probes, the generated double-stranded DNA (dsDNA) is constructed as a nanobridge, and the released G-rich sequence is folded into a G-quadruplex village. The fluorescence of crystal violet/G-quadruplex complex villages is enhanced by the dsDNA nanobridge connections. Under the excitation wavelength of 580 nm, the fluorescence emission intensity at 624 nm exhibits a good linearity with the concentration of crystal violet (CV) in the range of 10–250 nM, which can be used for sensitive detection of CV. Additionally, combined with Pb2+-dependent DNAzyme, a platform for quantitative detection of Pb2+ is established. In the concentration range of 5 nM – 25 μM, the fluorescence signal increases with the increase of Pb2+ concentration. The quantitative detection limit of Pb2+ by this method is 5 nM, and it possesses good selectivity and recovery for Pb2+ in a variety of water samples. More importantly, the platform can sensitively detect various metal ions by changing the DNAzyme sequence. It has potential application in the field of environmental monitoring.

Zircon LA-MC-ICP-MS U–Pb geochronology, major and trace element geochemistry, and Sr–Nd–Pb–Hf isotope analysis were performed on the Paleoproterozoic mafic dykes from the Wulashan area to investigate their petrogenesis and tectonic implications. The mafic dykes are diabase porphyries with a dominant mineral assemblage of plagioclase and clinopyroxene. Zircon U–Pb isotopic data yield weighted mean 207Pb/206Pb ages of 1769 ± 12 and 1770 ± 5 Ma for the NEE–EW trending and the N–S trending mafic dykes, respectively. Geochemically, these rocks belong to medium-K or high-K calc-alkaline series with K2O + Na2O contents of 3.39 to 5.28 wt.%. They show low MgO contents (3.92–4.63 wt.%) and Mg# values (32–37) and high contents of TiO2 (2.38–3.23 wt.%) and FeOt (13.60–15.29 wt.%). The dykes exhibit right-declined REE patterns, with (La/Yb)N of 4.63–9.35 and LREE/HREE of 5.02–7.92, and are characterized by enrichment in Rb, Ba, K, La, and Ce but depletion in Nb, Ta, Th, U, and Sr. Particularly, the NEE–EW trending samples display pronounced positive Ti anomalies, whereas the N–S trending samples exhibit negative P anomalies. All of the studied mafic dykes display similar Nd–Pb–Hf isotopic compositions with eNd(t) ranging from −3.41 to −1.49, (206Pb/204Pb)i of 15.0010 to 16.6626, (207Pb/204Pb)i of 15.2192 to 15.3468, (208Pb/204Pb)i of 35.0147 to 37.2389, and zircon eHf(t) values varying from −2.8 to 3.8. Geochemical modeling reveals that the NEE–EW and N–S trending mafic dykes were derived from 8% to 10% and 2%–4% partial melting of a common mantle source with ∼2% garnet. During emplacement, the parental mafic magma of the NEE–EW trending dykes experienced fractionation of clinopyroxene and accumulation of Ti–Fe oxides, whereas the N–S trending ones experienced fractionation of olivine and apatite. The selective enrichment of LILEs and LREEs, together with negative eNd(t) values and EMI-like Pb isotopic compositions, suggests that the dykes were derived from the partial melting of subcontinental lithospheric mantle metasomatized by slab-derived fluids. Furthermore, the marked depletion in Th and U and decoupled Nd–Hf isotopes indicate the incorporation of continental crustal components into the mantle prior to partial melting. Based on the geochemical features and previous regional geological data, we propose an extensional tectonic setting for the formation of the mafic dykes from the Wulashan area, possibly related to the post-orogenic setting following the collision between the Yinshan and Ordos Blocks.

Herein, a p-n quenching photoelectrochemical (PEC) biosensor is constructed for the ultrasensitive detection of miRNA-21 which the SnO2/CdCO3/CdS ternary composite nanomaterial is used as a signal indicator and the Y-type DNA structure stabilized p-type CuS quantum dot (QD) is employed as a signal quencher. Constructing the cascade energy level structure by using three photosensitive materials, in which stannic oxide (SnO2) is used as the photoactive material and cadmium sulfide (CdS) and cadmium carbonate (CdCO3) are served as the sensitizers. The prepared SnO2/CdCO3/CdS cascade co-sensitization structure with significantly improved photocurrent signal can inhibit the recombination of photogenerated electrons and holes, thereby dramatically enhancing the initial photocurrent response. Amounts of single strands DNA (assistant DNA) are output via the exponential strand displacement amplification (E-SDA) when miRNA-21 is present. The output assistant DNA can stabilize the CuS QD by forming stable Y-type DNA nanostructure on the surface of SnO2/CdCO3/CdS modified electrode. Therefore, the PEC signal of SnO2/CdCO3/CdS ternary composite nanomaterial is greatly quenched, because of the competitive consumption of exciting light energy and electron donors, as well as the steric effect of Y-type DNA structure. The linear range of the biosensor is from 10 fM to 1 μM with the detection limit down to 3.25 fM.

Based on the 7-nitro-1,2,3-benzoxadiazole (NBD) unit, many fluorescent probes have been developed for the differential detection of biothiols. Among them, however, the use of fluorescent probes for rapid simultaneous identification of biothiols in vivo has been rarely reported. In this work, a simple fluorescent probe (NC-NBD) is rationally designed and developed according to the different reactivity of biothiols, which can simultaneously distinguish homocysteine (Hcy), cysteine (Cys), and glutathione (GSH) by adjusting two different fluorescence signals (green and yellow). The probe NC-NBD can discriminatively detect biothiols using two fluorescence channels with fast response (120–360 s), which is suitable for real-time monitoring of biothiols in biological systems. As expected, the probe NC-NBD with excellent performance is able to determine the levels of Cys/Hcy and GSH in human serum samples, and therefore has potential applications in biological specimens. The robust probe shows low toxicity and high sensitivity when applied to living cells, and successfully achieves rapid sequence distinguishing of biothiols and intracellular imaging by using two different fluorescence signals. The probe can provide an effective tool for the real-time monitoring of intracellular biothiols.

Both organic and inorganic phosphates play important roles in biological activities. Considering the conventional methods are not very useful for identifying them from their analogues, the sensor array strategy has emerged in recent years, which is able to distinguish chemical species with similar structure or chemical properties. We propose a fluorescence sensor array based on two 3d-4f metal-organic frameworks (MOFs) by recording their direct one-step fluorescence changes with the addition of various phosphates. With the introduction of d-metal ions in the sensor unit synthesis process, two 3d-4f MOFs display higher sensitivity and noticeable fluorescence differences to five phosphates than the homometallic MOFs. Phosphates show diverse affinities to sensor units, forming the basis of differential sensing. The signals are much easier to collect, enabling the sensor array to simply accomplish the identification. Through statistical analysis, the sensor array is proved to be excellent in discriminating individual phosphate and mixture. Discrimination of five phosphates is successfully performed in serum samples to illustrate the practicability of the sensor array. This work presents an efficient and reliable approach for simultaneous detection of different phosphates, which can be extended to devise other array-based sensing methods.

Ionic liquid (IL) has attracted wide attention as a pretreating solvent for efficient utilization of lignocellulosic biomass. However, IL is known to severely inactivate the cellulases. In this study, the relative activity of Paenibacillus sp. LLZ1 cellulases (PCs) was analyzed in the presence of 1-ethyl-3-methylimidazolium diethylphosphate ([Emim]DEP) with respect to carboxymethylcellulose (CMC), filter paper (FP), and microcrystalline cellulose (MCC). With increasing [Emim]DEP concentration, PCs were differentially inhibited depending on the substrate. Subsequently, the kinetic parameters Km and Vmax were analyzed. A significant increase in the Km indicated that [Emim]DEP exerted a negative impact on the affinity of the enzyme on the substrate MCC. Comparatively, the Vmax was influenced only slightly. Further study on the relative MCCase activity with different substrate content showed that PCs were less inhibited at higher substrate concentration. Finally, sodium dodecyl sulfate polyacrylamide gel elec...

The newly discovered and large ca. 99 Ma Gaosongshan gold deposit is located in the Lesser Hinggan (or Xinggan) Range to the west of the Jiamusi Massif. The deposit is located at the border of the Great Hinggan Range–Mongolian Orogen with the Circum-Pacific tectonic belt and has a resource of ~ 22 t @ 6.3 g/t Au. Gaosongshan is classified as an adularia–sericite epithermal deposit associated with the large tensional Shaqihe Fault and has a low-sulfide content with a high concentration of gold hosted by pure chalcedonic quartz, which makes the deposit both unique and economically important in the area. Early Cretaceous volcanic rocks host the deposit as well as other gold deposits in the region. The mineralization at Gaosongshan includes Au, Ag, Mo, Sb, As, Pb and Hg. Stable isotope studies of fluid inclusions associated with the mineralization suggest that the mineralizing fluid had a meteoric origin (D V-SMOW : − 129 to − 111‰; 18 O fluid : 7.9 to 13.8‰). Fluid inclusion thermography indicates that the mineralized fluid was between 150° and 310 °C and had a low salinity (0.7–3.71 wt.% NaCl), low density (0.48–0.94 g/cm 3 ), shallow metallogenic depth (430–1270 m), and a large amount of reducing gaseous components (CH 4 , C 2 H 6 , CO, N 2 , and CO 2 ). The presence of large quantities of flaky quartz, adularia, gas-rich fluid inclusions, low-sulfide minerals and pure gold-bearing chalcedonic quartz suggests that fluid boiling was the principal mechanism for the gold precipitation. Sulfur isotopic data (δ 34 S: ~ − 2.4 to 2.9‰) indicate a deep magmatic origin for the mineralization, and the Pb isotopes ( 206 Pb/ 204 Pb: 18.14–18.46; 207 Pb/ 204 Pb: 15.51–15.57; 208 Pb/ 204 Pb: 38.01–38.40) also indicate that the metallogenic source of the deposit contained a significant mantle component. The mineralizing fluid interacted with a Late Paleozoic (ca. 260–253 Ma) substrate and ca. 141–91 Ma volcanic host rocks. The geological and geochemical characteristics of the deposit, and the Tuanjiegou, Dongan, Sandaowanzi and other large gold deposits represent an Early Cretaceous (114–80 Ma) epithermal mineralizing events in the Lesser Hinggan Range. The belt is controlled by the volcanic Sunwu–Jiayin Basin formed in a back-arc extensional setting along an active continental margin in East China, and the gold deposits in the belt have the same genesis as porphyritic Au(–Cu) deposits along the continental margin in eastern Jilin and Heilongjiang provinces. It is here proposed that the mineralization in both regions is related to the subduction of the Paleo-Pacific plate.

The age, petrogenesis and geodynamic implication of Xiaomiaogou granite porphyry dykes in the northern margin of the North China Craton were investigated using geochronology, geochemistry and Sr–Nd–Pb–Hf isotopic data. LA-MC-ICP-MS zircon U–Pb dating yielded the concordant 206Pb/238U weighted mean age of 350.4 ± 1.4 Ma for the dykes, suggesting they were the productions of the Early Carboniferous magmatism in the northern margin of the North China Craton. The granite porphyries display the pronounced A-type affinities: apart from higher zircon saturation temperature, they are high-K calc-alkaline and metaluminous, with high concentrations of K2O + Na2O varying from 7.93 to 8.55 wt.%, incompatible elements (e.g. Zr, Y, Nb and Ce), REEs and 10 000 Ga/Al ratios but less obvious LREE and HREE fractionation. With the lower initial 87Sr/86Sr ratios (0.7055 to 0.7070), negative values of eNd(t) (−7.1 to −4.9) and eHf(t) (−11.2 to −8.0) and old Nd (1505 to 1681 Ma) and Hf (1861 to 2061 Ma) model ages, all the rocks exhibit the similar geochemical compositions to the melts obtained in experimental studies by dehydration melting of meta-basalts, implying a lower continental crust origin. However, the high Mg# values (47.53 to 53.60) and subcontinental lithospheric mantle-like eNd(t), eHf(t) and Pb isotopic compositions ((206Pb/204Pb)i = 17.296–17.766, (207Pb/204Pb)i = 15.460–15.490 and (208Pb/204Pb)i = 37.097–37.568) indicate the involvement of melts from subcontinental lithospheric mantle. Combined with the special features of mafic microgranular enclaves occurring within the granite porphyries, mixing of the lower crust and subcontinental lithospheric mantle of the North China Craton is proposed for the genesis of granite porphyry dykes in this study. During the hybrid magma ascending, pronounced fractional crystallization and crustal assimilation may have also occurred. Based on geochemical criteria, the Xiaomiaogou granite porphyries can be classified into A1 group. Characterized by the compositional features of anorogenic granites, an intraplate setting is envisaged for the formation of Xiaomiaogou granite porphyry dykes. Such a tectonic environment may be related to the northward drift of the North China Craton during rifting away from East Gondwana. Copyright © 2016 John Wiley & Sons, Ltd.

The generation of free carriers in organic solar cells (OSCs) is very important. Free carriers in OSCs are generally contributed by the dissociation of excitons at the donor/acceptor interface. An n–n type device formed by two n-type materials was designed, and a new method was proposed to generate free carriers through the exciton–exciton interaction at the interface. However, the n–n type device shows poor performance because of weak exciton–exciton interaction at the interface. The interface design and optimization of the n–n type device will considerably influence and promote exciton–exciton interaction and ultimately allow the contribution of photocurrent to be determined. In this work, an effective Tris-8-hydroxy-quinolinato aluminum (Alq3) interface layer was introduced into the active layer of an n–n-type OSC to explore the exciton–exciton interaction that occurs at the perfluorphthalocyanine zinc/fullerene interface. The effect of various Alq3 thicknesses on the performance and external quantum efficiency (EQE) of devices was systematically investigated. The best performance for these n–n type OSCs was achieved at the 5 nm-thick Alq3 interface layer. The analysis of EQE measured under bias light further demonstrated that free carriers were contributed by exciton–exciton interaction. The EQE measured under different frequencies illustrated that the interaction of interfacial exciton–exciton was enhanced by the introduction of Alq3. A large displacement current was also generated in the Alq3 based on an n–n-type device.

In order to study the laser plasma instabilities (LPIs) in the context of some novel six-side laser-driven indirect designs like the six-cylinder-port hohlraum and the three-axis cylindrical hohlraum, where the laser beams inject in hohlraum with a large angle. LPI experiments in cylindrical hohlraum with only outer beams were designed and performed based on the current laser arrangement condition of SGIII laser facility for the first time. Stimulated Brillouin backscatter (SBS) was found to be the dominant instability with high instantaneous reflectivity in experiments. A typical feature was obtained in the time-resolved spectra of SBS, which maintained similar for different laser intensities of the interaction beam. The experimental data are analyzed by the hydrodynamic simulations combined with HLIP code, which is based on the ray-tracing model. By analysis of experimental data, it is argued that the mixture of gas and Au in the region of their interface is important to SBS, which indicates the need for the mixture model between the filled gas and the high Z plasma from hohlraum wall in the hydrodynamic simulations. Nonlinear saturation of SBS as well as the smoothed beam are also discussed here. Our effective considerations of the ions pervasion effect and the smoothed beam provide utilitarian ways for improvement of the current ray-tracing method.