Low-cost X-ray detectors with high performance, durability, and flexibility, are required for a wide range of applications in several fields, such as medical (diagnostic radiology, imaging, etc.), nondestructive testing (radioscopic inspections, radiography testing, etc.), security and defence (baggage/body scanning systems, paper mail, etc.), nuclear and radiation industries (nuclear power plants, research reactors, users of nuclear gauges, etc.), and research and development. [1] X-ray detection using semiconductors, based on the direct generation of electrical signals by X-rays (i.e., direct scheme), offers better spatial resolution and a simpler route than indirect schemes, in which X-rays are converted into photons by scintillating phosphors before detection by photodiode arrays. [2] Currently, the conventional materials used for direct conversion of X-rays include stabilized amorphous Se (α-Se), PbI 2 , HgI 2 , CdTe, and CdZnTe. [3] Metal halide perovskites represent a family of the most promising materials for fascinating photovoltaic and photodetector applications due to their unique optoelectronic properties and much needed simple and low-cost fabrication process. The high atomic number (Z) of their constituents and significantly higher carrier mobility also make perovskite semiconductors suitable for the detection of ionizing radiation. By taking advantage of that, the direct detection of soft-X-ray-induced photocurrent is demonstrated in both rigid and flexible detectors based on all-inorganic halide perovskite quantum dots (QDs) synthesized via a solution process. Utilizing a synchrotron soft-X-ray beamline, high sensitivities of up to 1450 µC Gy air −1 cm −2 are achieved under an X-ray dose rate of 0.0172 mGy air s −1 with only 0.1 V bias voltage, which is about 70-fold more sensitive than conventional α-Se devices. Furthermore, the perovskite film is printed homogeneously on various substrates by the inexpensive inkjet printing method to demonstrate large-scale fabrication of arrays of multichannel detectors. These results suggest that the perovskite QDs are ideal candidates for the detection of soft X-rays and for large-area flat or flexible panels with tremendous application potential in multidimensional and different architectures imaging technologies.

Summary Heterosis utilization is the most effective way to improve rice yields. The cytoplasmic male‐sterility (CMS) and photoperiod/thermosensitive genic male‐sterility (PTGMS) systems have been widely used in rice production. However, the rate of resource utilization for the CMS system hybrid rice is low, and the hybrid seed production for the PTGMS system is affected by the environment. The technical limitations of these two breeding methods restrict the rapid development of hybrid rice. The advantages of the genic male‐sterility (GMS) rice, such as stable sterility and free combination, can fill the gaps of the first two generations of hybrid rice technology. At present, the third‐generation hybrid rice breeding technology is being used to realize the application of GMS materials in hybrid rice. This study aimed to use an artificial CMS gene as a pollen killer to create a smart sterile line for hybrid rice production. The clustered regularly interspaced short palindromic repeats/CRISPR‐associated 9 (CRISPR/Cas9) technology was used to successfully obtain a CYP703A3‐deficient male‐sterile mutant containing no genetically modified component in the genetic background of indica 9311. Through young ear callus transformation, this mutant was transformed with three sets of element‐linked expression vectors, including pollen fertility restoration gene CYP703A3, pollen‐lethality gene orfH79 and selection marker gene DsRed2. The maintainer 9311‐3B with stable inheritance was obtained, which could realize the batch breeding of GMS materials. Further, the sterile line 9311‐3A and restorer lines were used for hybridization, and a batch of superior combinations of hybrid rice was obtained.

In article number 1901644, Babar Shabbir, Yupeng Zhang, Qiaoliang Bao, and co‐workers utilize inexpensive inkjet printing to homogeneously print a perovskite film consisting of all‐inorganic halide perovskite quantum dots on various substrates, which they further develop into an X‐ray detector. This type of detector is an ideal candidate for applications in soft/hard X‐ray detection and large‐area flat/flexible imaging technologies.

The absorption saturation under optically thick conditions will bring difficulties to laser spectroscopy gas sensing. We report the spectrum two wings reconstruction method and the transmitted laser intensity fitting method for tunable diode laser absorption saturation spectroscopy gas absolute measurements under optically thick conditions, and used the modified Lambert Beer's law to calculate methane concentration based on the incomplete spectrum of absorption saturation. The maximum deviation between the experimental measurement results and the standard methane concentration is about 4.7%, which verifies the feasibility of these new methods and also show that they have great potential for expanding the gas sensing range of a single absorption line.

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In this paper, an on-beam quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor based on a custom quartz tuning fork (QTF) acting as a photoacoustic transducer, was realized and tested. The QTF is characterized by a resonance frequency of 28 kHz, ~15% lower than that of a commercially available 32.7 kHz standard QTF. One-dimensional acoustic micro resonator (AmR) was designed and optimized by using stainless-steel capillaries. The 28 kHz QTF and AmRs are assembled in on-beam QEPAS configuration. The AmR geometrical parameters have been optimized in terms of length and internal diameter. The laser beam focus position and the AmR coupling distance were also adjusted to maximize the coupling efficiency. For comparison, QEPAS on-beam configurations based on a standard QTF and on the 28 kHz QTF were compared in terms of H 2 O and CO 2 detection sensitivity. In order to better characterize the performance of the system, H 2 O, C 2 H 2 and CO 2 were detected for a long time and the long-term stability was analyzed by an Allan variance analysis. With the integration time of 1 s, the detection limits for H 2 O, C 2 H 2 and CO 2 are 1.2 ppm, 28.8 ppb and 2.4 ppm, respectively. The detection limits for H 2 O, C 2 H 2 and CO 2 can be further improved to 325 ppb, 10.3 ppb and 318 ppb by increasing the integration time to 521 s, 183 s and 116 s

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Radial-cavity quartz-enhanced photoacoustic spectroscopy (RC-QEPAS) was proposed for trace gas analysis. A radial cavity with (0,0,1) resonance mode was coupled with the quartz tuning fork (QTF) to greatly enhance the QEPAS signal and facilitate the optical alignment. The coupled resonance enhancement effects of the radial cavity and QTF were analyzed theoretically and researched experimentally. With an optimized radial cavity, the detection sensitivity of QEPAS was enhanced by > 1 order of magnitude. The RC-QEPAS makes the acoustic detection module more compact and optical alignment comparable with a bare QFT, benefiting the usage of light sources with poor beam quality.