The effects of nitrogen and straw management on global warming potential (GWP) and greenhouse gas intensity (GHGI) in a winter wheat–summer maize double-cropping system on the North China Plain were ...investigated. We measured nitrous oxide (N2O) emissions and studied net GWP (NGWP) and GHGI by calculating the net exchange of CO2 equivalent (CO2-eq) from greenhouse gas emissions, agricultural inputs and management practices, as well as changes in soil organic carbon (SOC), based on a long-term field experiment established in 2006. The field experiment includes six treatments with three fertilizer N levels (zero N (control), optimum and conventional N) and straw removal (i.e. N0, Nopt and Ncon) or return (i.e. SN0, SNopt and SNcon). Optimum N management (Nopt, SNopt) saved roughly half of the fertilizer N compared to conventional agricultural practice (Ncon, SNcon), with no significant effect on grain yields. Annual mean N2O emissions reached 3.90 kg N2O-N ha−1 in Ncon and SNcon, and N2O emissions were reduced by 46.9% by optimizing N management of Nopt and SNopt. Straw return increased annual mean N2O emissions by 27.9%. Annual SOC sequestration was 0.40–1.44 Mg C ha−1 yr−1 in plots with N application and/or straw return. Compared to the conventional N treatments the optimum N treatments reduced NGWP by 51%, comprising 25% from decreasing N2O emissions and 75% from reducing N fertilizer application rates. Straw return treatments reduced NGWP by 30% compared to no straw return because the GWP from increments of SOC offset the GWP from higher emissions of N2O, N fertilizer and fuel after straw return. The GHGI trends from the different nitrogen and straw management practices were similar to the NGWP. In conclusion, optimum N and straw return significantly reduced NGWP and GHGI and concomitantly achieved relatively high grain yields in this important winter wheat–summer maize double-cropping system.
Occult peritoneal metastasis (PM) in advanced gastric cancer (AGC) patients is highly possible to be missed on computed tomography (CT) images. Patients with occult PMs are subject to late detection ...or even improper surgical treatment. We therefore aimed to develop a radiomic nomogram to preoperatively identify occult PMs in AGC patients.
A total of 554 AGC patients from 4 centers were divided into 1 training, 1 internal validation, and 2 external validation cohorts. All patients’ PM status was firstly diagnosed as negative by CT, but later confirmed by laparoscopy (PM-positive n = 122, PM-negative n = 432). Radiomic signatures reflecting phenotypes of the primary tumor (RS1) and peritoneum region (RS2) were built as predictors of PM from 266 quantitative image features. Individualized nomograms of PM status incorporating RS1, RS2, or clinical factors were developed and evaluated regarding prediction ability.
RS1, RS2, and Lauren type were significant predictors of occult PM (all P < 0.05). A nomogram of these three factors demonstrated better diagnostic accuracy than the model with RS1, RS2, or clinical factors alone (all net reclassification improvement P < 0.05). The area under curve yielded was 0.958 95% confidence interval (CI) 0.923–0.993, 0.941 (95% CI 0.904–0.977), 0.928 (95% CI 0.886–0.971), and 0.920 (95% CI 0.862–0.978) for the training, internal, and two external validation cohorts, respectively. Stratification analysis showed that this nomogram had potential generalization ability.
CT phenotypes of both primary tumor and nearby peritoneum are significantly associated with occult PM status. A nomogram of these CT phenotypes and Lauren type has an excellent prediction ability of occult PM, and may have significant clinical implications on early detection of occult PM for AGC.
One of the main material properties altered by rare earth additions in magnesium alloys is texture, which can be specifically adjusted to enhance ductility and formability. The current study aims at ...illuminating the texture selection process in a Mg–0.073at%Gd–0.165at%Zn alloy by investigating recrystallization nucleation and early nucleus growth during static recrystallization. An as-cast sample of the investigated alloy was deformed in uniaxial compression at 200 °C till 40% strain and was then cut into two halves for subsequent microstructure characterization via ex situ and quasi in situ EBSD investigations. In order to gain insights into the evolution of texture during recrystallization, the contributions from dynamic and static recrystallization were initially separated and the origin of the non-basal orientation of recrystallization nuclei was traced back to several potential nucleation sites within the deformed matrix. Considering the significant role of double-twin band recrystallization in determining the recrystallization texture, this type of recrystallization nucleation was further investigated via quasi-in situ EBSD on a deformed sample, annealed at 400 °C for different annealing times. With progressive annealing, a noticeable trend was observed, in which the basal nuclei gradually diminished and eventually vanished from the annealed microstructure. In contrast, the off-basal nuclei exhibited continuous growth, ultimately becoming the dominant contributors to the recrystallization texture. The study therefore emphasizes the importance of particular nucleation sites that generate favorably oriented off-basal nuclei, which over the course of recrystallization outcompete the neighboring basal-oriented nuclei in terms of growth and thereby dominate the recrystallization texture.
We discovered stripe patterns of trimerization-ferroelectric domains in hexagonal REMnO(3) (RE=Ho,···,Lu) crystals (grown below ferroelectric transition temperatures (T(c)), reaching up to 1435 °C), ...in contrast with the vortex patterns in YMnO(3). These stripe patterns roughen with the appearance of numerous loop domains through thermal annealing just below T(c), but the stripe domain patterns turn to vortex-antivortex domain patterns through a freezing process when crystals cross T(c) even though the phase transition appears to not be Kosterlitz-Thouless-type. The experimental systematics are compared with the results of our six-state clock model simulation and also the Kibble-Zurek mechanism for trapped topological defects.
Polymeric metal coagulants are increasingly being used to improve coagulation efficiency, yet the research on the development of titanium and particularly polytitanium salts remains limited. This ...study is the first attempt in the synthesis, characterization, and application of polytitanium salts as coagulants. Polytitanium tetrachloride (PTC) solutions with different basicity values B (OH/Ti molar ratio) were prepared using a slow alkaline titration method. Jar tests were conducted to assess coagulation performance using both synthetic and real raw water samples, and the floc characteristics were monitored online using a laser diffraction particle size analyzer. Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) was utilized to identify various Ti species, with the results providing strong evidence of the presence of various hydrolyzed Ti species in the titanium aqueous phase. Compared to titanium tetrachloride (TiCl4), higher or comparable turbidity and organic matter removal efficiency could be achieved by PTC with improved floc characteristics in terms of size, growth rate, and structure. Besides, the water pH after PTC coagulation was significantly improved toward neutral pH. This study indicates that PTC is an effective and promising coagulant for water purification. Besides, the PTC flocculated sludge was able to recycle and produce functional TiO2 photocatalyst.
In this study, the performance of titanium tetrachloride (TiCl
4) coagulation and flocculation is compared with commonly used coagulants such as aluminum sulfate (Al
2(SO
4)
3), polyaluminum chloride ...(PACl), iron chloride (FeCl
3), and polyferric sulfate (PFS) in terms of water quality parameters and floc properties. TiCl
4 flocculation achieved higher removal of UV
254 (98%), dissolved organic carbon (DOC) (84%) and turbidity (93%) than other conventional coagulants. Charge neutralization and physical entrapment of colloids within coagulant precipitates and adsorption, seemed to play a significant role during TiCl
4 flocculation, while the main mechanism for conventional coagulants was bridge-aggregation and adsorption. The aggregated flocs after TiCl
4 flocculation showed the fastest growth rate compared to the other coagulants, with the largest floc size (801
μm) occurring within 8
min. The floc strength factor of PACl, Al
2(SO
4)
3, PFS, FeCl
3 and TiCl
4 was 34, 30, 29, 26 and 29, respectively, while the floc recovery factor of the TiCl
4 coagulant was the lowest. Based on the results of the above study, it is concluded that the TiCl
4 flocculation can reduce the hydraulic retention time of slow and rapid mixing, however, careful handling of sludge is required due to the low recoverability of the aggregated floc.
Polymerized inorganic coagulants are increasingly being used in the water supply and wastewater treatment process, yet there is limited research on the development of polytitanium coagulants. The aim ...of this study is to synthesize polytitanium chloride (PTC) coagulants and investigate their coagulation behavior and floc characteristics for humic acid removal in comparison to polyaluminum chloride (PAC). The PTC samples with different B (molar ratios of OH/Ti) values were prepared using an instantaneous base-feeding method, employing sodium carbonate as the basification agent. The coagulation efficiency was significantly influenced by different B values. The results suggest that the humic acid removal increased with the increasing B value for PAC, while the inverse trend was observed for PTC. The optimum B value was chosen at 1.0 and 2.0 for PTC and PAC, respectively. Under the optimum coagulant dose and initial solution pH conditions, the PTC coagulant performed better than the PAC coagulant and the floc properties were significantly improved in terms of floc growth rate and floc size. However, the PAC coagulants produced flocs with better floc recoverability than the PTC coagulants.
The kinetic floc growth, breakage and regrowth profiles with different flocculants: Display omitted
•Stable PTC coagulants were synthesized employing Na2CO3 as the basification agent.•Coagulation behavior of PTC was comparatively investigated against PAC.•PTC performs better than PAC in terms of organic matter removal and floc properties.•PTC is an efficient and promising coagulant for water purification.
Background
Around 20 years ago, a 60‐ to 70‐kDa protein was reported as a major allergen of mugwort (Artemisia vulgaris) pollen. This study was to identify and characterize its molecular properties.
...Methods
Sera from 113 Chinese and 20 Dutch Artemisia‐allergic/sensitized subjects (and pools thereof) were used to identify the 60‐ to 70‐kDa allergen. Pollen extracts of seven Artemisia species were compared by immunoblotting. Transcriptomics and proteomics (mass spectrometry) of A. annua pollen were used to identify the putative 60‐ to 70‐kDa Artemisia allergen. Both the natural purified and recombinant allergens were evaluated for IgE reactivity by ImmunoCAP. Fourteen Chinese Artemisia‐allergic patients were tested intradermally with purified natural allergen.
Results
Immunoblots revealed two major bands at 12 and 25 kDa, and a weak band at 70 kDa for all seven Artemisia species. Using a combined transcriptomic and proteomic approach, the high molecular mass allergen in A. annua pollen was shown to be a 62‐kDa putative galactose oxidase, with a putative N‐glycosylation site. More than 94% of Artemisia pollen‐allergic patients had IgE response to this allergen. Although recognition of a nonglycosylated recombinant version was only confirmed in a minority (16%) and at much lower IgE levels, this discrepancy cannot be explained simply by reactivity to the carbohydrate moiety on the natural allergen. Intradermal testing with the natural allergen was positive in five of nine sensitized patients.
Conclusions
The previously reported 60‐ to 70‐kDa allergen of Artemisia pollen is most likely a 62‐kDa putative galactose oxidase here designated Art an 7.
•Flame stability limits increased with increasing thermal conductivities.•Flame stability limits increased with decreasing pore density.•Flame temperatures of 30PPI SiC foams are lower than its ...counterparts.•CO emission of 30PPI foams was notably lower than its counterparts.•HC emission increased in the order of 20, 25, 30, and 10PPI foams.
Selecting appropriate materials is the most important consideration in designing a porous medium burner. The choice determines the performance and service life of the burner. The premixed combustion of methane/air in a two-layer burner packed with 3mm-diameter alumina (Al2O3) beads at the upstream section and cellular foam at the downstream section was studied. Cellular foam was selected as the alternative material for alumina, zirconia (ZrO2), iron–chromium–aluminum (FeCrAl), or silicon carbide (SiC). The flame stability, flame temperature profile, flame temperature, pressure drop, and pollutant emission of these four materials were investigated. The effect of pore density on SiC foam was also discussed. Results indicated that flame stability limits expanded with increased foam conductivities but shrank with increased pore density. Carbon monoxide (CO) emission was not sensitive to the materials (S>30cm/s). The CO emission of 30pores per inch (PPI) foams was notably lower than that of foams with other pore densities because of the higher flame temperature. Hydrocarbon (HC) concentration was almost constant for ZrO2, Al2O3, and FeCrAl foams. However, the HC concentration of SiC foams decreased with increased flame speed. HC emission increased in the order of 20, 25, 30, and 10PPI foams. Nitrogen oxide (NOx) emission was relatively low (below 3ppm) because of low flame temperature.
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