Efficient oxidative degradation of 2-chlorophenol and 4-chlorophenol over supported CuO-based catalysts

A series of metal oxide catalysts for catalytic oxidative degradation of 2-chlorophenol （2-CP） and 4-chlorophenol （4-CP） were prepared, and the supported CuO catalysts were studied particularly. The supported CuO catalysts were characterized by XRD and NH3-TPD techniques, in which CuO/γ-Al2O3 exhibited high degradation activity. The addition of Na2O or K2O into CuO/γ-Al2O3 improved the oxidative degradation of CPs remarkably, in which Na2O was more efficient than K2O. Over CuO/γ-Al2O3-Na2O, CPs were completely converted and the liberation of the inorganic chloride from 2-CP or 4-CP reached 97% or 100% respectively at 30 ？C for 2 h. The supported CuO catalysts with good dispersion of CuO particles and less acid sites were favorable for the efficient oxidative degradation of CPs. In addition, the initial pH of the reaction solution was found to be an important factor which influenced the catalytic oxidative degradation of CPs and the initial pH of 11.2 and 9.8 was preferred for the oxidative degradation of 2-CP and 4-CP respectively over CuO/γ-Al2O3 catalyst.

Atomization characteristics of pyrolysis oil derived from waste tires

The atomization characteristics play a key role in the highly efficient combustion of pyrolysis oil derived from waste tires.In this study,the fuel properties of tire pyrolysis oil(TPO)were initially studied,and then a high-speed camera and a phase Doppler particle analyzer were employed to characterize the atomization feature of TPO.The influence of pressure and nozzle orifice diameter on atomization characteristics such as spray angle,droplet velocity,and droplet size distribution was investigated.The results showed that TPO had a high calorific value of about 43.6 MJ/kg and a low viscosity of 3.84×10^(–6)m^(2)/s at 40℃,which made it have the potential to be used as an alternative fuel.Higher pressure expanded the spray angle and extended the spray in both the axial and radial directions.With increasing pressure,spray angle and droplet velocity raised,and the increase in crushing effect of air reduced the Sauter mean diameter(SMD)of the droplets.To obtain proper atomization quality for combustion,the pressure is expected to be higher than 1.25 MPa.With increasing nozzle orifice diameter,droplet velocity increased,and the SMD of the droplets increased as well due to weakened crushing effect of the orifice.Therefore,the pressure must be increased to maintain the atomization quality when using a nozzle with a larger orifice.Due to the lower viscosity,the velocity and particle size distribution of TPO droplets after atomization were smaller than those of diesel droplets.The extremely small carbon black contained in TPO also contributed to the breaking of droplets and played a certain role in the size reduction of the oil droplets,but it may cause the risk of nozzle blockage.In summary,TPO showed great atomization characteristics for alternative fuel applications.

GmCRY1s modulate gibberellin metabolism to regulate soybean shade avoidance in response to reduced blue light

Soybean is an important legume crop that displays the classic shade avoidance syndrome(SAS),including exaggerated stem elongation,which leads to lodging and yield reduction under density farming conditions.Here,we compared the effects of two shade signals,low red light to far-red light ratio(R:FR)and low blue light(LBL),on soybean status and revealed that LBL predominantly induces excessive stem elongation.We used CRISPR-Cas9-engineered Gmcry mutants to investigate the functions of seven cryptochromes(GmCRYs)in soybean and found that the four GmCRY1s overlap in mediating LBL-induced SAS.Lightactivated GmCRY1s increase the abundance of the bZlP transcription factors STF1 and STF2,which directly upregulate the expression of genes encoding GA2 oxidases to deactivate GA1 and repress stem elongation.Notably,GmCRY1b overexpression lines displayed multiple agronomic advantages over the wild-type control under both dense planting and intercropping conditions.Our study demonstrates the integration of GmCRY1-mediated signals with the GA metabolic pathway in the regulation of LBL-induced SAS in soybean.It also provides a promising option for breeding lodging-resistant,high-yield soybean cultivars in the future.

Experimental study and numerical simulation of the characteristics of a percussive gas-solid separator

The presence of solid particles in the flow of hypersonic wind tunnels damages the appearance of the experiment models in the wind tunnel and influences the accuracy of experimental results. The design of a highly efficient gas-solid separator was therefore undertaken, Particle trajectory imaging methods were used to measure trajectories under different conditions. The flow field and particle movement characteristics for different head angles （HAs） and separation tooth angles （STAs）, inlet velocities, and the exhaust gas outlet pressures in the separator, were calculated using simulations based on the discrete phase model. The particle separation efficiency, pressure loss, and flow loss resulting from different structural parameters were also studied. In line with experimental observations, the characteristic angle of particle movements in the separator and the separation efficiency of the separator were found to increase with decreasing HA and with increasing STA. Separation efficiency improves with increasing inlet velocity and with increasing negative pressure of the exhaust gas outlet; however, the corresponding pressure loss and the flow rate of the waste gas also increased.

Pyroptotic macrophages stimulate the SARS-CoV-2-associated cytokine storm

Coronavirus disease 2019(COVID-19)is an unprecedented pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).As of 22 February 2021,the worldwide pandemic has resulted in more than 110 million cases and 2.4 million deaths.1 Clinical investigation of COVID-19 patients has shown that a systemic cytokine storm can occur,especially in severe cases.2 Treatment of the SARS-CoV-2-associated cytokine storm with tocilizumab3 or anakinra4 has been shown to immediately improve the clinical outcome in most severe and critical COVID-19 patients.These data highlight the systemic cytokine storm as an important exacerbating event in severe COVID-19;however,our understanding of the molecular mechanisms involved in the initiation of the SARS-CoV-2-associated cytokine storm is limited.In the present study,we uncovered a reasonable explanation for cytokine storm initiation through the analysis of 13 autopsy samples from severe COVID-19 patients.

Tocilizumab in patients with moderate or severe COVID-19: a randomized, controlled, open-label, multicenter trial

Tocilizumab has been reported to attenuate the“cytokine storm”in COVID-19 patients.We attempted to verify the effectiveness and safety of tocilizumab therapy in COVID-19 and identify patients most likely to benefit from this treatment.We conducted a randomized,controlled,open-label multicenter trial among COVID-19 patients.The patients were randomly assigned in a 1:1 ratio to receive either tocilizumab in addition to standard care or standard care alone.The cure rate,changes of oxygen saturation and interference,and inflammation biomarkers were observed.Thirty-three patients were randomized to the tocilizumab group,and 32 patients to the control group.The cure rate in the tocilizumab group was higher than that in the control group,but the difference was not statistically significant(94.12%vs.87.10%,rate difference 95%CI−7.19%–21.23%,P=0.4133).The improvement in hypoxia for the tocilizumab group was higher from day 4 onward and statistically significant from day 12(P=0.0359).In moderate disease patients with bilateral pulmonary lesions,the hypoxia ameliorated earlier after tocilizumab treatment,and less patients(1/12,8.33%)needed an increase of inhaled oxygen concentration compared with the controls(4/6,66.67%;rate difference 95%CI−99.17%to−17.50%,P=0.0217).No severe adverse events occurred.More mild temporary adverse events were recorded in tocilizumab recipients(20/34,58.82%)than the controls(4/31,12.90%).Tocilizumab can improve hypoxia without unacceptable side effect profile and significant influences on the time virus load becomes negative.For patients with bilateral pulmonary lesions and elevated IL-6 levels,tocilizumab could be recommended to improve outcome.

Transcriptomic characteristics and impaired immune function of patients who retest positive for SARS-CoV-2 RNA

Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection,has become a global public health crisis.Some patients who have recovered from COVID-19 subsequently test positive again for SARS-CoV-2 RNA after discharge from hospital.How such retest-positive(RTP)patients become infected again is not known.In this study,30 RTP patients,20 convalescent patients,and 20 healthy controls were enrolled for the analysis of immunological characteristics of their peripheral blood mononuclear cells.We found that absolute numbers of CD4^(+)T cells,CD8^(+)T cells,and natural killer cells were not substantially decreased in RTP patients,but the expression of activation markers on these cells was significantly reduced.The percentage of granzyme B-producing T cells was also lower in RTP patients than in convalescent patients.Through transcriptome sequencing,we demonstrated that high expression of inhibitor of differentiation 1(ID1)and low expression of interferon-induced transmembrane protein 10(IFITM10)were associated with insufficient activation of immune cells and the occurrence of RTP.These findings provide insight into the impaired immune function associated with COVID-19 and the pathogenesis of RTP,which may contribute to a better understanding of the mechanisms underlying RTP.