Impacts of Future Climate Change on Net Primary Productivity of Grassland in Inner Mongolia, China

Net Primary Productivity (NPP) of grassland is a key variable of terrestrial ecosystems and is an important parameter for characterizing carbon cycles in grassland ecosystems. In this research, the Inner Mongolia grassland NPP was calculated using the Miami Model and the impact of climate change on grassland NPP was subsequently analyzed under the Special Report on Emissions Scenarios (SRES) A2, B2, and A1B scenarios, which are inferred from Providing Regional Climates for Impacts Studies (PRECIS) climate model system. The results showed that: (1) the NPP associated with these three scenarios had a similar distribution in Inner Mongolia: the grassland NPP increased gradually from the western region, with less than 200 g/m2/yr, to the southeast region, with more than 800 g/m2/yr. Precipitation was the main factor determining the grassland NPP; (2) compared with the baseline (1961-1990), there would be an overall increase in grassland NPP during three time periods (2020s: 2011-2040, 2050s: 2041-2070, and 2080s: 2071-2100) under the A2 and B2 scenarios; (3) under the A1B scenario, there will be a decreasing trend at middle-west region during the 2020s and 2050s; while there will be a very significant decrease from the 2050s to 2080s for middle Inner Mongolia; and (4) grassland NPP under the A1B scenario would present the most significant increase among the three scenarios, and would have the least significant increase under the B2 scenario

PdCu nanoalloy decorated photocatalysts for efficient and selective oxidative coupling of methane in flow reactors

Methane activation by photocatalysis is one of the promising sustainable technologies for chemical synthesis. However, the current efficiency and stability of the process are moderate. Herein, a PdCu nanoalloy (~2.3 nm) was decorated on TiO2, which works for the efficient, stable, and selective photocatalytic oxidative coupling of methane at room temperature. A high methane conversion rate of 2480 μmol g-1 h-1 to C2 with an apparent quantum efficiency of ~8.4% has been achieved. More importantly, the photocatalyst exhibits the turnover frequency and turnover number of 116 h-1 and 12,642 with respect to PdCu, representing a record among all the photocatalytic processes (λ > 300 nm) operated at room temperature, together with a long stability of over 112 hours. The nanoalloy works as a hole acceptor, in which Pd softens and weakens C-H bond in methane and Cu decreases the adsorption energy of C2 products, leading to the high efficiency and long-time stability

Recurrent paratesticular giant liposarcoma: A case report and literature review

BackgroundPrimary paratesticular liposarcoma is rarely diagnosed among urinary tumors. In this study, through the retrospective analysis of clinical data and literature review, a case of recurrent paratesticular liposarcoma with lymph node metastasis after radical resection has been reported to explore novel strategies for the diagnosis, treatment and prognosis of this rare disease.Case summaryThe present case involved a patient who was misdiagnosed as a left inguinal hernia for the first time two years ago, but was later diagnosed as mixed liposarcoma by using postoperative pathology. Currently, he is readmitted to the hospital with a recurrence of the left scrotal mass for more than 1 year. Combined with the patient's past medical history, we performed radical resection of the left inguinal and scrotal tumors and lymphadenectomy of left femoral vein. The postoperative pathology indicated that well-differentiated liposarcoma was accompanied by mucinous liposarcoma (about 20%), and lymph node metastasis of left femoral vein both of which occurred at the same time. After the operation, we recommended the patient to receive further radiation therapy, but the patient and his family refused, hence we followed up the patient closely for a long time. During the recent follow-up, the patient reported no complaints of discomfort, and no recurrence of mass in the left scrotum and groin area.ConclusionAfter conducting extensive review of literature, we conclude that radical resection remains the key to treat primary paratesticular liposarcoma, while the significance of the lymph node metastasis is still unclear. The potential effects of postoperative adjuvant therapy depends on the pathological type, and hence close follow-up observation is essential

Reciprocal facilitation between annual plants and burrowing crabs:Implications for the restoration of degraded saltmarshes

Increasing evidence shows that facilitative interactions between species play an essential role in coastal wetland ecosystems. However, there is a lack of understanding of how such interactions can be used for restoration purposes in saltmarsh ecosystems. We therefore studied the mechanisms of reciprocal facilitative interactions between native annual plants, Suaeda salsa, and burrowing crabs, Helice tientsinensis, in a middle-elevation saltmarsh (with generally high plant density and moderate tides) in the Yellow River Delta of China. We investigated the relationship between the densities of the plants and crab burrows in different seasons. Then, we tested whether and how saltmarsh plants and crabs indeed facilitate each other in a series of field and laboratory experiments. Finally, we applied the results by creating a field-scale artificial approach for microtopographic modification to restore a degraded saltmarsh. We found that the density of plant seedlings in spring was positively correlated with the density of crab burrows in the previous autumn; moreover, the density of crab burrows was correlated with the density of plants in summer. The concave-convex surface microtopography created by crabs promoted seed retention and seedling establishment of saltmarsh plants in winter and spring. These plants in turn facilitated crabs by inhibiting predators, providing food and reducing physical stresses for crabs in summer and autumn. The experimental removal of saltmarsh plants decreased crab burrow density, while both transplanting and simulating plants in bare patches promoted crabs. The microtopographic modification, inspired by our new understanding of the interactions between saltmarsh plants and crabs, showed that these degraded saltmarsh ecosystems can be restored by a single ploughing intervention. Synthesis. Our results suggest a reciprocal facilitation between annual plants and burrowing crabs in a middle-elevation saltmarsh ecosystem. This knowledge yielded new restoration options for degraded coastal saltmarshes through the one-time ploughing initiation of microtopographic variation, which could promote the re-establishment of ecosystem engineers and lead to the efficient recovery of pioneer coastal vegetation and associated fauna

CuInS2 sensitized TiO2 hybrid nanofibers for improved photocatalytic CO2 reduction

Photocatalytic CO2 reduction into solar fuels over photocatalysts has theoretically and practically become a hot research topic. Herein, we fabricated a novel hybrid TiO2 nanofiber coated by CuInS2 nanoplates through a hydrothermal method. The materials were characterized by X-ray diffraction, electron microscopes, UV-vis absorption spectra, nitrogen sorption, X-ray photoelectron spectroscopy and electrochemical impudence spectroscopy. The resulting TiO2/CuInS2 hybrid nanofibers exhibit superior photocatalytic activity for CO2 reduction under irradiation, due to the generation of direct Z-scheme heterojunction between TiO2 and CuInS2. This work may provide an alternate methodology to design and fabricate multicomponent TiO2-based photocatalyst for high-efficiency CO2 photoreduction

1D/2D TiO2/MoS2 hybrid nanostructures for enhanced photocatalytic CO2 reduction

Photocatalytic reduction of CO2 into solar fuels is recognized an attractive approach to solve the environmental and energy crisis. MoS2, a type of 2D transition metal dichalcogenides, has attracted significant attention in photoelectronics, sensors and photo/electrocatalytic water splitting owing to its remarkable properties. Nevertheless, to date, MoS2 is barely used as (co)catalyst for CO2 photoreduction. Herein, novel 1D/2D TiO2/MoS2 nanostructured hybrid with TiO2 fibers covered by MoS2 nanosheets by hydrothermal transformation method is fabricated. The MoS2 sheet arrays show a lateral size of ≈80 nm and a thickness of down to 2 nm, vertically and uniformly standing upon the TiO2 fibers. X‐ray photoelectron spectroscopy (XPS) results and density functional theory (DFT) calculation imply the intimate chemical interaction between MoS2 and TiO2 upon hybridization, which can facilitate electron–hole separation upon photoexcitation. In addition, the hierarchical TiO2/MoS2 nanostructure shows enhanced optical absorption and CO2 adsorption, therefore, a superior photocatalytic activity for reducing CO2 into methane and methanol is achieved over the hybrid as compared to pristine TiO2. Isotope (13C) tracer test confirms that the products are produced from the photocatalytic reduction of the CO2 source instead of any organic contaminants. This work offers an alternative approach to rationally design and synthesize TiO2‐based photocatalysts toward high‐efficiency photoreduction of CO2

Electrospun TiO2-Based Photocatalysts

Solar-driven semiconductor photocatalysis shows great potential to solve growing energy and environmental crises. Electrospun TiO2 nanofibers (NFs) attract attention due to their chemical stability, nontoxicity, cheapness, large specific surface area, and porous structures. The unique unwoven nanofibrous network facilitates mass transportation compared with bulk materials. Electrospun TiO2 NFs are an ideal substrate for growing secondary nanostructures and constructing heterojunction photocatalysts. The hybrid heterojunctions show enhanced electron–hole separation, improved light absorption, effective activation of reactants, and therefore increased photocatalytic performance. Herein, the electrospinning principle and preparing tactics of electrospun TiO2 fibrous nanostructures including solid, hollow, and core/shell NFs are first described. The construction strategies of electrospun TiO2-based heterojunctions by loading electron or hole cocatalysts and hybridizing secondary semiconductors to engineer catalytic active sites and steer charge carrier separation are outlined. Dopant-induced increased light absorption and enhanced charge transfer of TiO2 NFs are discussed. Further, the applications of electrospun TiO2-based photocatalysts for solar-to-chemical conversion and environmental remediation are elucidated. Finally, the challenges and perspectives for the development of electrospun TiO2-based photocatalysts are underlined, which deepen a systematic understanding of the design and fabrication of more efficient electrospun NFs in the future.</p

Graphdiyne: A new photocatalytic CO2 reduction cocatalyst

Exploring new and efficient cocatalysts to boost photocatalytic CO2 reduction is of critical importance for solar‐to‐fuel conversion. As an emerging carbon allotrope, graphdiyne (GDY) features 2D characteristics and unique carbon–carbon bonds. Herein, a novel GDY cocatalyst coupled TiO2 nanofibers for boosted photocatalytic CO2 reduction, synthesized by an electrostatic self‐assembly approach is reported. First‐principle calculation and in situ X‐ray photoelectron spectroscopy measurement reveal that the delocalized electrons in GDY can hybrid with the empty orbitals in TiO2 within the TiO2/GDY network, leading to the formation of an internal electric field at the interfaces, pointing from GDY to TiO2. The theoretical simulation further implies strong chemisorption and deformation of CO2 molecules upon GDY, which can be verified by in situ diffuse reflectance infrared Fourier transform spectroscopy. These effects, in combination with the photothermal effect of GDY, result in enhanced charge separation and directed electron transfer, enhanced CO2 adsorption and activation as well as accelerated catalytic reactions over the TiO2/GDY heterostructure, thereby resulting in significantly improved CO2 photoreduction efficiency and meanwhile with remarkable selectivity. This work demonstrates that GYD can function as a highly effective cocatalyst for solar energy harvesting and may be used in other catalysis processes