[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of fo...[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of four functional organic materials,namely garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),on the morphological indexes,yield and quality of watermelon were investigated.[Results]Different functional organic materials had different effects on morphological indexes,yield and quality of watermelon.The morphological indexes,nutritional quality indexes and yield of watermelon treated with garlic straw and sheep manure compound(T_(3))and onion straw and chicken manure compound(T_(4))were significantly higher than those treated simply with garlic straw(T_(1))and onion straw(T_(2)),and T_(3)performed relatively better.Compared with treatment T_(2),T_(3)showed a stem diameter,vine length and leaf number increasing by 43.05%,46.69%and 40.77%respectively,central sugar and side sugar contents increasing by 11.72%and 21.90%respectively,and a yield increasing by 42.91%,with significant differences from T_(2).[Conclusions]This study provides technical support for high-quality and high-yielding cultivation of watermelon.展开更多
Colored rice is a type of high-quality,high-added-value rice that has attracted increasing attention in recent years.The use of large amounts of inorganic nitrogen fertilizer in rice fields results in low fertilizer u...Colored rice is a type of high-quality,high-added-value rice that has attracted increasing attention in recent years.The use of large amounts of inorganic nitrogen fertilizer in rice fields results in low fertilizer use efficiency and high environmental pollution.Organic fertilizer is a promising way to improve soil quality and sustain high yields.However,most studies focus on the effect of animal-based organic fertilizers.The effects of different ratios of plantbased organic fertilizer and inorganic fertilizer on the grain yield and quality of colored rice have rarely been reported.Therefore,a two-year field experiment was conducted in 2020 and 2021 to study the effects of replacing inorganic N fertilizers with plant-based organic fertilizers on the yield,nitrogen use efficiency(NUE),and anthocyanin content of two colored rice varieties in a tropical region in China.The experimental treatments included no nitrogen fertilization(T1),100% inorganic nitrogen fertilizer(T2),30%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T3),60%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T4),and 100% plantbased organic fertilizer(T5).The total nitrogen provided to all the treatments except T1 was the same at 120 kg ha-1.Our results showed that the T3 treatment enhanced the grain yield and anthocyanin content of colored rice by increasing nitrogen use efficiency compared with T2.On average,grain yields were increased by 9 and 8%,while the anthocyanin content increased by 16 and 10% in the two colored rice varieties under T3 across the two years,respectively,as compared with T2.Further study of the residual effect of partial substitution of inorganic fertilizers showed that the substitution of inorganic fertilizer with plant-based organic fertilizer improved the soil physiochemical properties,and thus increased the rice grain yield,in the subsequent seasons.The highest grain yield of the subsequent rice crop was observed under the T5 treatment.Our results suggested that the application of plantbased organic fertilizers can sustain the production of colored rice with high anthocyanin content in tropical regions,which is beneficial in reconciling the relationship between rice production and environmental protection.展开更多
Olive productivity should be improved through stimulating nutrition,particularly under poor fertility soils.Consequently,the objective of this study was to assess the efficacy of applying organic and bio-fertilizers o...Olive productivity should be improved through stimulating nutrition,particularly under poor fertility soils.Consequently,the objective of this study was to assess the efficacy of applying organic and bio-fertilizers on the physiological growth,yield and fruit quality of olive trees under newly reclaimed poor-fertility sandy soil in an arid environment.During a field experiment carried out at El-Qantara,North Sinai,Egypt over two consecutive seasons(2019-2020 and 2020-2021),olive Kalamata trees were evaluated under three organic fertilizer treatments alone or in combination with three bio-fertilizers treatments.Organic fertilizer was applied as goat manure(16.8 kg/tree/year),or olive pomace(8.5 kg/tree/year)in mid-December of each season vs.untreated trees.The bio-fertilizers were applied as N-fixing bacteria(150 g/tree)was inculated in early March of each season,or amino acid mixture(1.5%)was applied three times,at 70%of full bloom,21 days after full bloom,and a month later in comparison to a non-fertilized trees(control).The cultivar used was Kalamata,a dual-purpose cultivar for oil and table olives whose value increases when processed as table olives.The results indicated that the goat manure followed by olive pomace significantly enhanced photosynthetic pigments(chlorophyll a,b,and carotenoids),leaf mineral contents(N,P,K,Ca,Mg and Fe),tree canopy volume,number of flowers per inflorescence,number of inflorescences per shoot,initial fruit set,fruit retention.For fruit quality,fruit length and width,fruit weight,and total fruit yield was increased compared to the non-fertilized control.Likewise,The bio-fertilizer N-fixing bacteria followed by the amino acid mixture significantly improved all of the aforementioned parameters.Accordingly,it is recommended,both environmentally and economically to utilize organic and bio-fertizers,particularly goat manure combined with N-fixing bacteria,in low-fertility soil to sustain olive production as well as reducing mineral fertilization.展开更多
Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil...Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl.展开更多
BACKGROUND Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery.They are venous clusters formed by con-gestion,expansion,and flexion of the venous plexus in ...BACKGROUND Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery.They are venous clusters formed by con-gestion,expansion,and flexion of the venous plexus in the lower part of the rec-tum.Mixed hemorrhoids bleed easily and recurrently,and this can result in severe anemia.Hence,they may have a negative effect on the health of the patient and surgical treatment is required.Milligan-Morgan hemorrhoidectomy has been widely used since 1937 for the treatment of grade III and IV hemorrhoids.How-ever,most patients experience different degrees of postoperative pain that may cause anxiety.with mixed hemorrhoids post-surgery.METHODS The clinical data of patients with mixed hemorrhoids who underwent Milligan-Morgan hemorrhoidectomy were collected retrospectively.The basic character-istics of the enrolled patients with mixed hemorrhoids were recorded,and based on the Goligher clinical grading system,the hemorrhoids were classified as grades III or IV.The endpoint of this study was the disappearance of pain in all patients.Quantitative data were presented as mean±SD,such as age,pain score,and QoL score.Student’s t-test was used to compare the groups.RESULTS A total of 164 patients were enrolled.The distribution of the visual analog scale pain scores of all patients at 3,7,14 and 28 d after surgery showed that post-surgery pain was significantly reduced with the passage of time.Fourteen days after the operation,the pain had completely disappeared in some patients.Twenty-eight days after the surgery,none of the patients experienced any pain.Comparing the World Health Or-ganization Quality of Life-BREF self-reporting questionnaire scores of patients between 14 and 28 d after surgery,we observed that the quality-of-life scores of the patients post-surgery had significantly improved.There were six items that were compared at 14-and 28-d post-surgery.The mean QoL score 28 d after surgery(4.79±0.46)was higher than that at 14 d post-surgery(3.79±0.57).The mean health condition score 28 d after surgery(4.80±0.41)was also higher than that at 14 d post-surgery(4.01±0.62).The mean physical health score 28 d after surgery(32.10±2.96)was significantly higher than that at 14 d post-surgery(23.41±2.85).The mean psychological health score 28 d after surgery(27.22±1.62)was significantly higher than that at 14 d post-surgery(21.37±1.70).The mean social relations score 28 d after surgery(12.21±1.59)was significantly higher than that at 14 d post-surgery(6.32±1.66).The mean surrounding environment score 28 d after surgery(37.13±2.88)was significantly higher than that at 14 d post-surgery(28.42±2.86).The differences in quality-of-life scores at day 14 and day 28 post-surgery were ob-served to be statistically significant(P<0.001).CONCLUSION Milligan-Morgan hemorrhoidectomy can significantly improve the postoperative QoL of patients.Age,sex,and the number of surgical resections were important factors influencing Milligan-Morgan hemorrhoidectomy.展开更多
The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were anal...The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were analyzed by using variance analysis,significance test and other methods.The release efficiency of organic fertilizer in the soil was slower,and the effect of organic fertilizer on the growth of tobacco plants was worse than that of chemical fertilizers,and under 25% organic fertilizer + 75% chemical fertilizer treatment,the quality of the fluecured tobacco was good.Under the treatment of 50% organic fertilizer + 50% chemical fertilizer,the production of flue-cured tobacco was high and the ratio of first-class tobacco was high.It is suggested that the organic fertilizer application ratio should be 25%-50% in the agricultural production.展开更多
A bentonite-humic acid(B-HA) mixture added to degraded soils may improve soil physical and hydraulic properties, due to effects such as improved soil structure and increased water and nutrient retention, but its effec...A bentonite-humic acid(B-HA) mixture added to degraded soils may improve soil physical and hydraulic properties, due to effects such as improved soil structure and increased water and nutrient retention, but its effect on soil physicochemical and biological properties, and grain quality is largely unknown. The effect of B-HA, added at 30 Mg ha^(-1), was studied at 1,3, 5 and 7 years after its addition to a degraded sandy soil in a semi-arid region of China. The addition of B-HA significantly increased water-filled pore space and soil organic carbon, especially at 3 to 5 years after its soil addition to the soil. Amending the sandy soil with B-HA also increased the content of microbial biomass(MB)-carbon,-nitrogen and-phosphorus, and the activities of urease, invertase, catalase and alkaline phosphatase. The significant effect of maize(Zea mays L.) growth stage on soil MB and enzyme activities accounted for 58 and 84% of their total variation, respectively. In comparison, B-HA accounted for 8% of the total variability for each of the same two variables. B-HA significantly enhanced soil properties and the uptake of N and P by maize in semi-arid areas. The use of B-HA product would be an effective management strategy to reclaim degraded sandy soils and foster sustainable agriculture production in northeast China and regions of the world with similar soils and climate.展开更多
In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars,...In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars, organic acids and flavor quality of bagged Fuji fruit were studied. The results showed that the 5 pollination varieties had significant metaxenia effects on sugars, organic acids and flavor quality of bagged Fuji fruit. For the sugar components, the fruits pollinated with Golden Delicious and Jinxiuhaitang showed higher glucose contents, and the fruit pollinated with Gala had the highest sucrose content; the fruits pollinated by Gala, Golden Delicious and Ruby exhibited higher malic acids, and the oxalic acid content and the succinic acid content were higher in the fruits pollinated with Jinxiuhaitang and Ruby ; and the fruit pollinated with Gala had the highest total sugar content, and the total acid content was higher in the fruits pollinated by Jinxiuhaitang and Ruby. The sugar-acid ratio was higher in the fruits pollinated with Gala and Golden Delicious, and the lowest in the fruit pollinated with Ruby. The senso- ry evaluation of fruits showed that the fruit pollinated with Ruby tasted sour-sweet, while the fruits pollinated with other 4 pollination varieties were sour and sweet moderately.展开更多
The proper use of organic and inorganic nutrient sources is important to sustain high levels of crop production, while maintaining or enhancing soil and environmental quality. A 4-year (2009 to 2012) field experiment ...The proper use of organic and inorganic nutrient sources is important to sustain high levels of crop production, while maintaining or enhancing soil and environmental quality. A 4-year (2009 to 2012) field experiment was established in spring 2009 on a Gray Luvisol (Typic Haplocryalf) loam soil at Star City, Saskatchewan, Canada, to determine the effectiveness of organic/biological (compost, wood ash [fine and granular], alfalfa pellets, distiller grain, thin stillage, glycerol, fish food additive, Penicillium bilaiae), inorganic/mineral (granular-gypsum, rapid release elemental S [RRES], rock phosphate [granular and fine]) and chemical/synthetic (granular-ammonium nitrate, triple super phosphate and potassium sulphate) nutrient sources (amendments/chemicals) in improving seed yield, straw yield, seed quality and nutrient uptake (N, P, K and S) in seed + straw of canola. Combined application of N, P and S chemical fertilizers (NPS) produced considerably greater seed yield, straw yield and nutrient uptake of canola compared to the unamended control in all four years. In treatments receiving only organic amendments, thin stillage produced the greatest seed yield, straw yield and nutrient uptake in all years, and it was similar to the NPS balanced fertilizer treatment, while fish food additive and distiller grain dry of wheat in 2009, 2011 and 2012, distiller grain dry of corn in 2009 and 2012, and compost and alfalfa pellets in 2011 and 2012 produced significantly greater seed yield, straw yield and nutrient uptake, when compared to the control. In treatments where chemical fertilizers were also applied, in addition to organic amendments, ap- plication of N fertilizer increased seed yield, straw yield and nutrient uptake substantially when combined with wood ash fine in 2009, 2010, 2011 and 2012, wood ash granular in 2009, 2011 and 2012, and glycerol in 2009 and 2012 (moderate increase in 2012). In the chemical fertilizer treatments, there was a reduction in seed yield, straw yield and nutrient uptake of canola when only N fertilizer was applied compared to the control (significant in 2010 and 2011). Application of P along with N (NP) increased seed yield, straw yield and nutrient uptake of canola compared to N alone treatment, but was less than the NPS treatment in all years. Application of S along with N (NS) increased seed yield, straw yield and nutrient uptake of canola further compared to the NP treatment, but it was still lower than the NPS treatment in 2010 and 2011. In treatments receiving inorganic/mineral amendments in addition to chemical fertilizers, application of N + P fertilizers substantially increased seed yield, straw yield and nutrient uptake in treatments receiving gypsum and RRES in 2009, 2010, 2011 and 2012. This suggests the potential of gypsum and RRES in preventing S deficiency in organic crops when grown on S-deficient soils, provided other nutrients are not limiting in the soil for crop growth. Seed yield, straw yield and nutrient uptake with application of N and S fertilizers in combination with rock phosphate and/or Penicillium bilaiae were similar to N + S treatment in most cases, except in 2011 when application of finely-ground or powder rock phosphate in a combination with N + S produced significantly greater yield and nutrient uptake than N + S with granular rock phosphate. This suggests little contribution of rock phosphate and/or Penicillium bilaiae in improving yield and nutrient uptake of canola, and improves the performance of fine rock phosphate only evident in the third growing season in 2011, after three consecutive applications, but not in 2012. In conclusion, some organic amendments showed potential for improvement in organic crop production, and in some other cases highest yield and nutrient uptake were展开更多
Concentrations of airborne particulate matter (PM10 & PM2.5) were measured over a period extended from January 2012 to October 2013 at two sites: a suburban area, Riyadh airport (AP) and an urban area, King Fahd r...Concentrations of airborne particulate matter (PM10 & PM2.5) were measured over a period extended from January 2012 to October 2013 at two sites: a suburban area, Riyadh airport (AP) and an urban area, King Fahd road district (KF) (densely trafficked site) in Riyadh city, Saudi Arabia. The quality of ambient air using the U.S. Environmental Protection Agency (USEPA) Air Quality Index (AQI) was evaluated during this period. The average AQI values exceeded 100 on 6 months out of 11 in AP district. At KF district the condition was worse, and AQI values exceeded 100 on all months. This emphasizes the fact that PM concentrations over Riyadh can be regarded as a real environmental problem that could be a severe risk to quality of life and threaten human health. A higher-volume air sampler at the two sites was used to collect particulate matter (PM10 and PM2.5) for chemical analysis of the PM for PAHs and total organic carbon. At KF station the mean concentrations’ values of total PAHs in PM2.5 and PM10 were 4.89 ng/m<sup>3</sup> and 12.96 ng/m<sup>3</sup> respectively. At the AP station the corresponding values of total PAHs in PM2.5 and PM10 were 8.07 ng/m<sup>3</sup> and 11.91 ng/m<sup>3</sup> respectively. The PAHs did not exceed the air criteria of World Health Organization indicating the air pollution of PAHs in Riyadh District was not serious. As for the total organic carbon the results demonstrated that the concentration ranged from 0.211 to 0.506 g/kg at KF station and from 0.054 to 0.342 g/kg at AP station. On an annual basis, OC concentrations were two times higher for the city center site (KF) compared to the rural AP site. This can most likely be explained by increased emissions from higher traffic at KF site. The diurnal variability of PM was mainly associated with the severity of pollution.展开更多
Boleophthalmus pectinirostris is an amphibious economic fish and wildly distributed in the southeast coast of China. In this study, Aroclor 1254 was intraperitoneally injected into B. pectinirostris with 1, 2 and 4 ...Boleophthalmus pectinirostris is an amphibious economic fish and wildly distributed in the southeast coast of China. In this study, Aroclor 1254 was intraperitoneally injected into B. pectinirostris with 1, 2 and 4 μg/(g · d) for 28 d to assay the reproductive organ weight, the sperm quality (sperm concentration and motility), and the testicular mitochondrial testicular mitochondria oxidative stress. The results show that the sperm number and motility in seminal vesicles, the absolute weight of testes and seminal vesicles of B. pectinirostris treated with 2 and 4 μg/(g · d) Aroclor 1254 decreased significantly as compared to the controls (p 0.05), while those treated with 1 μg/(g · d) Aroclor 1254 had no significant effects on these indictors. For the relative weight of reproductive organs, significant reduction (p 0.05) was only observed in the seminal vesicles of B. pectinirostris treated with 4 μg/(g · d). SOD activities and GSH levels in all the Aroclor 1254 treatments were significantly lower than those of the controls (p 0.05). The activities of CAT, GPx, GR and the levels of Vit C also decreased significantly in comparison with the controls (p 0.05) at the higher dose of 2 and 4 μg/(g · d) Aroclor 1254 treatments. In addition, both H 2 O 2 level and MDA content in testicular mitochondria of B. pectinirostris had a close correlation with Aroclor 1254 dosage, and were significantly higher than the controls (p 0.05). Those indicate that Aroclor 1254 can induce the oxidative stress of testicular mitochondria, and impair the reproductive function of male B. pectinirostris.展开更多
Dietary polyphenols, or phenolic compounds, are numerous, diverse, and ubiquitous phytochemicals occurring throughout the plant kingdom. They are important components of the human diet because of their capacity to red...Dietary polyphenols, or phenolic compounds, are numerous, diverse, and ubiquitous phytochemicals occurring throughout the plant kingdom. They are important components of the human diet because of their capacity to reduce the risk of chronic diseases such as cardiovascular disease and cancer. In plants, polyphenols contribute to resistance to pathogens due to their potent astringency and function as phytoalexins. As a result, organic grapevines grown with reduced pesticides may be more stressed by pathogens than conventionally grown grapevines and presumably produce more polyphenols. Since polyphenols also play an important role in the sensory qualities of fruits and wines particularly involving astringency and bitterness, there may be differences that affect sensory perceptions of wine. This establishes a conundrum where dietary polyphenols are healthful but potentially unpalatable.We recruited and randomized 18 female participants (21 - 50 y) to one of five groups (3 - 4 per group). Each group evaluated the sensory qualities of a geographically paired organic (OW) and conventional wine (CW) and an artificially colored white wine placebo (PW) with significantly differing total polyphenol concentrations (TP). Participants reported for three visits (one wine per visit) where they consumed 5 ounces (150 mL) of wine over 15 minutes while completing the sensory survey. Sensory evaluations based on a Likert-type scale included visual, aroma, and taste perceptions and overall impressions (scale 0 - 10). In two wine pairs, the OW contained significantly more TP (3.49 and 5.86 g/L) than the respective CW (2.63 and 4.63 g/L). In two other wine pairs both produced by sustainable viticulture, the CW (5.23 and 8.38 g/L) contained sig- nificantly more TP than OW (4.55 and 3.70 g/L) and in one set the amounts were equivalent (4.10 and 4.17 g/L). The five PW averaged 1.26 ± 0.20 g/L. Although there were significant differences in TP content of test wines, the results indicated that no significant differences in either intensity or quality for any of the sensory qualities were detected be- tween paired OW and CW wines but both scored significantly higher than the PW, with significantly lower TP. We conclude in this pilot study that a subset of OW from the Southwestern US is perceived similarly to CW produced by the same vineyard even with significantly differing TP concentrations.展开更多
This article conducts a brief analysis of the factors that affect the quality safety of organic mango, and discusses the organic production measures for improving the quality and quality safety of mango, including the...This article conducts a brief analysis of the factors that affect the quality safety of organic mango, and discusses the organic production measures for improving the quality and quality safety of mango, including the choice of environment of place of origin, varieties and seedlings, fertilizers and fertilization, plant protection products and other production inputs. A test is carried out in 0.667 hm2 of base in Tianyang County, Baise City. Content of lead, arsenic and 14 kinds of pesticide residue such as BHC in the mango are not detected; the content of heavy metal such as mercury and cadmium is 0.001-0.006 mg/kg. Then the quality and quality safety indicators of organic mango are discussed, and finally the Guangxi local standards of organic mango products are developed.展开更多
Field experiments were conducted at Tamil Nadu Agricultural University, Coimbatore during rabi and summer seasons of 2007-2008 and 2008-2009 to study the influence of organic manures (enriched farmyard manure compost,...Field experiments were conducted at Tamil Nadu Agricultural University, Coimbatore during rabi and summer seasons of 2007-2008 and 2008-2009 to study the influence of organic manures (enriched farmyard manure compost, vermicompost, farmyard manure + neem cake, enriched farmyard manure compost + vermicompost + farmyard manure, composted poultry manure and enriched poultry manure compost) and recommended NPK fertilizers on yield and quality of rice and blackgram in rice-blackgram cropping sequence. Based on field experiments, it was found that the application of enriched poultry manure compost on equal N basis (2.3 t·ha-1) recorded higher yield attributes and grain yield of rice (4675 kg·ha-1 in 2007 and 4953 kg·ha-1 in 2008), which was however comparable with composted poultry manure. The application of recommended NPK fertilizers recorded higher physical characteristics and cooking qualities of rice, which was comparable with enriched poultry manure compost. Higher sensory score was registered in enriched poultry manure compost as compared to recommended NPK through fertilizers. After harvesting of rice, the residual effect of enriched poultry manure compost and composted poultry manure applied to preceding rice crop improved yield attributes and yield of succeeding blackgram.展开更多
The effect of a self-organized SiNs interlayer on the defect density of (1122) semipolar GaN grown on 7n-plane sapphire is studied by transmission electron microscopy, atomic force microscopy and high resolution x-r...The effect of a self-organized SiNs interlayer on the defect density of (1122) semipolar GaN grown on 7n-plane sapphire is studied by transmission electron microscopy, atomic force microscopy and high resolution x-ray diffrac- tion. The SiNx interlayer reduces the c-type dislocation density from 2.5 ×10^10 cm^-2 to 5 ×10^8 cm 2. The SiNx interlayer produces regions that are free from basal plane stacking faults (BSFs) and dislocations. The overall BSF density is reduced from 2.1×10^5 cm-1 to 1.3×10^4 cm^-1. The large dislocations and BSF reduction in semipolar (1122) GaN with the SiNx, interlayer result from two primary mechanisms. The first mechanism is the direct dislocation blocking by the SiNx interlayer, and the second mechanism is associated with the unique structure character of (1122) semipolar GaN.展开更多
A new approach to coastal water quality assessment was put forward through study on self-organizing map (SOM). Firstly, the water quality data of Bohai Bay from 1999 to 2002 were prepared. Then, a set of software for ...A new approach to coastal water quality assessment was put forward through study on self-organizing map (SOM). Firstly, the water quality data of Bohai Bay from 1999 to 2002 were prepared. Then, a set of software for coastal water quality assessment was developed based on the batch version algorithm of SOM and SOM toolbox in MATLAB environment. Furthermore, the training results of SOM could be analyzed with single water quality indexes, the value of N: P( atomic ratio) and the eutrophication index E so that the data were clustered into five different pollution types using k-means clustering method. Finally, it was realized that the monitoring data serial trajectory could be tracked and the new data be classified and assessed automatically. Through application it is found that this study helps to analyze and assess the coastal water quality by several kinds of graphics, which offers an easy decision support for recognizing pollution status and taking corresponding measures.展开更多
基金Supported by Shangqiu Science and Technology Research Project(202405).
文摘[Objectives]This study was conducted to explore suitable organic compound application models for watermelon growth.[Methods]With watermelon hybrid material"M22×P18"as the test material,the effects of four functional organic materials,namely garlic straw treatment(T_(1)),onion straw treatment(T_(2)),garlic straw+sheep manure treatment(T_(3))and onion straw+chicken manure treatment(T_(4)),on the morphological indexes,yield and quality of watermelon were investigated.[Results]Different functional organic materials had different effects on morphological indexes,yield and quality of watermelon.The morphological indexes,nutritional quality indexes and yield of watermelon treated with garlic straw and sheep manure compound(T_(3))and onion straw and chicken manure compound(T_(4))were significantly higher than those treated simply with garlic straw(T_(1))and onion straw(T_(2)),and T_(3)performed relatively better.Compared with treatment T_(2),T_(3)showed a stem diameter,vine length and leaf number increasing by 43.05%,46.69%and 40.77%respectively,central sugar and side sugar contents increasing by 11.72%and 21.90%respectively,and a yield increasing by 42.91%,with significant differences from T_(2).[Conclusions]This study provides technical support for high-quality and high-yielding cultivation of watermelon.
基金supported by the National Natural Science Foundation of China(32060430 and 31971840)the Research Initiation Fund of Hainan University,China(KYQD(ZR)19104)。
文摘Colored rice is a type of high-quality,high-added-value rice that has attracted increasing attention in recent years.The use of large amounts of inorganic nitrogen fertilizer in rice fields results in low fertilizer use efficiency and high environmental pollution.Organic fertilizer is a promising way to improve soil quality and sustain high yields.However,most studies focus on the effect of animal-based organic fertilizers.The effects of different ratios of plantbased organic fertilizer and inorganic fertilizer on the grain yield and quality of colored rice have rarely been reported.Therefore,a two-year field experiment was conducted in 2020 and 2021 to study the effects of replacing inorganic N fertilizers with plant-based organic fertilizers on the yield,nitrogen use efficiency(NUE),and anthocyanin content of two colored rice varieties in a tropical region in China.The experimental treatments included no nitrogen fertilization(T1),100% inorganic nitrogen fertilizer(T2),30%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T3),60%inorganic nitrogen fertilizer substitution with plant-based organic fertilizer(T4),and 100% plantbased organic fertilizer(T5).The total nitrogen provided to all the treatments except T1 was the same at 120 kg ha-1.Our results showed that the T3 treatment enhanced the grain yield and anthocyanin content of colored rice by increasing nitrogen use efficiency compared with T2.On average,grain yields were increased by 9 and 8%,while the anthocyanin content increased by 16 and 10% in the two colored rice varieties under T3 across the two years,respectively,as compared with T2.Further study of the residual effect of partial substitution of inorganic fertilizers showed that the substitution of inorganic fertilizer with plant-based organic fertilizer improved the soil physiochemical properties,and thus increased the rice grain yield,in the subsequent seasons.The highest grain yield of the subsequent rice crop was observed under the T5 treatment.Our results suggested that the application of plantbased organic fertilizers can sustain the production of colored rice with high anthocyanin content in tropical regions,which is beneficial in reconciling the relationship between rice production and environmental protection.
基金The authors extend their appreciation to the Deanship of Scientific Research at Jouf University for funding this work through Research Grant No.(DSR2020-01-2553).
文摘Olive productivity should be improved through stimulating nutrition,particularly under poor fertility soils.Consequently,the objective of this study was to assess the efficacy of applying organic and bio-fertilizers on the physiological growth,yield and fruit quality of olive trees under newly reclaimed poor-fertility sandy soil in an arid environment.During a field experiment carried out at El-Qantara,North Sinai,Egypt over two consecutive seasons(2019-2020 and 2020-2021),olive Kalamata trees were evaluated under three organic fertilizer treatments alone or in combination with three bio-fertilizers treatments.Organic fertilizer was applied as goat manure(16.8 kg/tree/year),or olive pomace(8.5 kg/tree/year)in mid-December of each season vs.untreated trees.The bio-fertilizers were applied as N-fixing bacteria(150 g/tree)was inculated in early March of each season,or amino acid mixture(1.5%)was applied three times,at 70%of full bloom,21 days after full bloom,and a month later in comparison to a non-fertilized trees(control).The cultivar used was Kalamata,a dual-purpose cultivar for oil and table olives whose value increases when processed as table olives.The results indicated that the goat manure followed by olive pomace significantly enhanced photosynthetic pigments(chlorophyll a,b,and carotenoids),leaf mineral contents(N,P,K,Ca,Mg and Fe),tree canopy volume,number of flowers per inflorescence,number of inflorescences per shoot,initial fruit set,fruit retention.For fruit quality,fruit length and width,fruit weight,and total fruit yield was increased compared to the non-fertilized control.Likewise,The bio-fertilizer N-fixing bacteria followed by the amino acid mixture significantly improved all of the aforementioned parameters.Accordingly,it is recommended,both environmentally and economically to utilize organic and bio-fertizers,particularly goat manure combined with N-fixing bacteria,in low-fertility soil to sustain olive production as well as reducing mineral fertilization.
文摘Assessing soil organic carbon stock (SOCS) and soil quality (SQ) helps design better agricultural practices to improve environmental sustainability and productivity. The purpose of the study is to assess SOCS and soil quality SQ in the main agroecosystems (AES) of the eastern flank of Mount Bambouto (West, Cameroon). Using multiple statistics tests and principal component analysis (PCA), SOCS and Soil Quality Index (SQI) were computed for each AES. SOCS and SQI were computed based on soil chemical properties and analysis of variance. Topsoil samples (0 - 30 cm) were collected in a different AES and analyzed in the laboratory. The four AES identified and selected are cultivated land (CL), forest areas (FA), mixed areas (MA), and bush areas (BA). Further, multiple comparison tests were used to compare soils from different AES. PCA was used to select the most appropriate indicators that control SOCS and SQ. Several soil properties showed high to very high coefficient of variation within the AES. Organic matter (OM) was significantly high in FA. SOCS and SQ differ significantly (p = 0.000) between the AES. The study further indicates that the main variables controlling SQ within the eastern flank of Mount Bambouto are OM, pHw, N, C/N, and CEC. While the main soil parameters controlling SOCS are OM, OC, BD, C/N, S, and pHKCl.
文摘BACKGROUND Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery.They are venous clusters formed by con-gestion,expansion,and flexion of the venous plexus in the lower part of the rec-tum.Mixed hemorrhoids bleed easily and recurrently,and this can result in severe anemia.Hence,they may have a negative effect on the health of the patient and surgical treatment is required.Milligan-Morgan hemorrhoidectomy has been widely used since 1937 for the treatment of grade III and IV hemorrhoids.How-ever,most patients experience different degrees of postoperative pain that may cause anxiety.with mixed hemorrhoids post-surgery.METHODS The clinical data of patients with mixed hemorrhoids who underwent Milligan-Morgan hemorrhoidectomy were collected retrospectively.The basic character-istics of the enrolled patients with mixed hemorrhoids were recorded,and based on the Goligher clinical grading system,the hemorrhoids were classified as grades III or IV.The endpoint of this study was the disappearance of pain in all patients.Quantitative data were presented as mean±SD,such as age,pain score,and QoL score.Student’s t-test was used to compare the groups.RESULTS A total of 164 patients were enrolled.The distribution of the visual analog scale pain scores of all patients at 3,7,14 and 28 d after surgery showed that post-surgery pain was significantly reduced with the passage of time.Fourteen days after the operation,the pain had completely disappeared in some patients.Twenty-eight days after the surgery,none of the patients experienced any pain.Comparing the World Health Or-ganization Quality of Life-BREF self-reporting questionnaire scores of patients between 14 and 28 d after surgery,we observed that the quality-of-life scores of the patients post-surgery had significantly improved.There were six items that were compared at 14-and 28-d post-surgery.The mean QoL score 28 d after surgery(4.79±0.46)was higher than that at 14 d post-surgery(3.79±0.57).The mean health condition score 28 d after surgery(4.80±0.41)was also higher than that at 14 d post-surgery(4.01±0.62).The mean physical health score 28 d after surgery(32.10±2.96)was significantly higher than that at 14 d post-surgery(23.41±2.85).The mean psychological health score 28 d after surgery(27.22±1.62)was significantly higher than that at 14 d post-surgery(21.37±1.70).The mean social relations score 28 d after surgery(12.21±1.59)was significantly higher than that at 14 d post-surgery(6.32±1.66).The mean surrounding environment score 28 d after surgery(37.13±2.88)was significantly higher than that at 14 d post-surgery(28.42±2.86).The differences in quality-of-life scores at day 14 and day 28 post-surgery were ob-served to be statistically significant(P<0.001).CONCLUSION Milligan-Morgan hemorrhoidectomy can significantly improve the postoperative QoL of patients.Age,sex,and the number of surgical resections were important factors influencing Milligan-Morgan hemorrhoidectomy.
基金Supported by Yunnan Tobacco Company Project(2015YN19,2014YN25)
文摘The effect of different ratio of organic and inorganic fertilizers on the growth and the yield and quality of flue-cured tobacco was studied.Using randomized blocks design,the data of the test materials K326 were analyzed by using variance analysis,significance test and other methods.The release efficiency of organic fertilizer in the soil was slower,and the effect of organic fertilizer on the growth of tobacco plants was worse than that of chemical fertilizers,and under 25% organic fertilizer + 75% chemical fertilizer treatment,the quality of the fluecured tobacco was good.Under the treatment of 50% organic fertilizer + 50% chemical fertilizer,the production of flue-cured tobacco was high and the ratio of first-class tobacco was high.It is suggested that the organic fertilizer application ratio should be 25%-50% in the agricultural production.
基金financial support provided by the National Special Fund for Agro-scientific Research in the Public Interest of China(201303126)Agricultural Science and Technology Achievements Transformation Demonstration of Production and Application Technology and Popularization of Sandy Soil Amendment,Inner Mongolia,China(sq2012eca400008)。
文摘A bentonite-humic acid(B-HA) mixture added to degraded soils may improve soil physical and hydraulic properties, due to effects such as improved soil structure and increased water and nutrient retention, but its effect on soil physicochemical and biological properties, and grain quality is largely unknown. The effect of B-HA, added at 30 Mg ha^(-1), was studied at 1,3, 5 and 7 years after its addition to a degraded sandy soil in a semi-arid region of China. The addition of B-HA significantly increased water-filled pore space and soil organic carbon, especially at 3 to 5 years after its soil addition to the soil. Amending the sandy soil with B-HA also increased the content of microbial biomass(MB)-carbon,-nitrogen and-phosphorus, and the activities of urease, invertase, catalase and alkaline phosphatase. The significant effect of maize(Zea mays L.) growth stage on soil MB and enzyme activities accounted for 58 and 84% of their total variation, respectively. In comparison, B-HA accounted for 8% of the total variability for each of the same two variables. B-HA significantly enhanced soil properties and the uptake of N and P by maize in semi-arid areas. The use of B-HA product would be an effective management strategy to reclaim degraded sandy soils and foster sustainable agriculture production in northeast China and regions of the world with similar soils and climate.
基金Supported by Major Agricultural Applied Technology Innovation Project of Shandong Province(2014)Agricultural Science and Technology Innovation Project of Shandong Academy of Agricultural Sciences(CXGC2016B07)Earmarked Fund for China Agriculture Research System(CARS-28)
文摘In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars, organic acids and flavor quality of bagged Fuji fruit were studied. The results showed that the 5 pollination varieties had significant metaxenia effects on sugars, organic acids and flavor quality of bagged Fuji fruit. For the sugar components, the fruits pollinated with Golden Delicious and Jinxiuhaitang showed higher glucose contents, and the fruit pollinated with Gala had the highest sucrose content; the fruits pollinated by Gala, Golden Delicious and Ruby exhibited higher malic acids, and the oxalic acid content and the succinic acid content were higher in the fruits pollinated with Jinxiuhaitang and Ruby ; and the fruit pollinated with Gala had the highest total sugar content, and the total acid content was higher in the fruits pollinated by Jinxiuhaitang and Ruby. The sugar-acid ratio was higher in the fruits pollinated with Gala and Golden Delicious, and the lowest in the fruit pollinated with Ruby. The senso- ry evaluation of fruits showed that the fruit pollinated with Ruby tasted sour-sweet, while the fruits pollinated with other 4 pollination varieties were sour and sweet moderately.
文摘The proper use of organic and inorganic nutrient sources is important to sustain high levels of crop production, while maintaining or enhancing soil and environmental quality. A 4-year (2009 to 2012) field experiment was established in spring 2009 on a Gray Luvisol (Typic Haplocryalf) loam soil at Star City, Saskatchewan, Canada, to determine the effectiveness of organic/biological (compost, wood ash [fine and granular], alfalfa pellets, distiller grain, thin stillage, glycerol, fish food additive, Penicillium bilaiae), inorganic/mineral (granular-gypsum, rapid release elemental S [RRES], rock phosphate [granular and fine]) and chemical/synthetic (granular-ammonium nitrate, triple super phosphate and potassium sulphate) nutrient sources (amendments/chemicals) in improving seed yield, straw yield, seed quality and nutrient uptake (N, P, K and S) in seed + straw of canola. Combined application of N, P and S chemical fertilizers (NPS) produced considerably greater seed yield, straw yield and nutrient uptake of canola compared to the unamended control in all four years. In treatments receiving only organic amendments, thin stillage produced the greatest seed yield, straw yield and nutrient uptake in all years, and it was similar to the NPS balanced fertilizer treatment, while fish food additive and distiller grain dry of wheat in 2009, 2011 and 2012, distiller grain dry of corn in 2009 and 2012, and compost and alfalfa pellets in 2011 and 2012 produced significantly greater seed yield, straw yield and nutrient uptake, when compared to the control. In treatments where chemical fertilizers were also applied, in addition to organic amendments, ap- plication of N fertilizer increased seed yield, straw yield and nutrient uptake substantially when combined with wood ash fine in 2009, 2010, 2011 and 2012, wood ash granular in 2009, 2011 and 2012, and glycerol in 2009 and 2012 (moderate increase in 2012). In the chemical fertilizer treatments, there was a reduction in seed yield, straw yield and nutrient uptake of canola when only N fertilizer was applied compared to the control (significant in 2010 and 2011). Application of P along with N (NP) increased seed yield, straw yield and nutrient uptake of canola compared to N alone treatment, but was less than the NPS treatment in all years. Application of S along with N (NS) increased seed yield, straw yield and nutrient uptake of canola further compared to the NP treatment, but it was still lower than the NPS treatment in 2010 and 2011. In treatments receiving inorganic/mineral amendments in addition to chemical fertilizers, application of N + P fertilizers substantially increased seed yield, straw yield and nutrient uptake in treatments receiving gypsum and RRES in 2009, 2010, 2011 and 2012. This suggests the potential of gypsum and RRES in preventing S deficiency in organic crops when grown on S-deficient soils, provided other nutrients are not limiting in the soil for crop growth. Seed yield, straw yield and nutrient uptake with application of N and S fertilizers in combination with rock phosphate and/or Penicillium bilaiae were similar to N + S treatment in most cases, except in 2011 when application of finely-ground or powder rock phosphate in a combination with N + S produced significantly greater yield and nutrient uptake than N + S with granular rock phosphate. This suggests little contribution of rock phosphate and/or Penicillium bilaiae in improving yield and nutrient uptake of canola, and improves the performance of fine rock phosphate only evident in the third growing season in 2011, after three consecutive applications, but not in 2012. In conclusion, some organic amendments showed potential for improvement in organic crop production, and in some other cases highest yield and nutrient uptake were
文摘Concentrations of airborne particulate matter (PM10 & PM2.5) were measured over a period extended from January 2012 to October 2013 at two sites: a suburban area, Riyadh airport (AP) and an urban area, King Fahd road district (KF) (densely trafficked site) in Riyadh city, Saudi Arabia. The quality of ambient air using the U.S. Environmental Protection Agency (USEPA) Air Quality Index (AQI) was evaluated during this period. The average AQI values exceeded 100 on 6 months out of 11 in AP district. At KF district the condition was worse, and AQI values exceeded 100 on all months. This emphasizes the fact that PM concentrations over Riyadh can be regarded as a real environmental problem that could be a severe risk to quality of life and threaten human health. A higher-volume air sampler at the two sites was used to collect particulate matter (PM10 and PM2.5) for chemical analysis of the PM for PAHs and total organic carbon. At KF station the mean concentrations’ values of total PAHs in PM2.5 and PM10 were 4.89 ng/m<sup>3</sup> and 12.96 ng/m<sup>3</sup> respectively. At the AP station the corresponding values of total PAHs in PM2.5 and PM10 were 8.07 ng/m<sup>3</sup> and 11.91 ng/m<sup>3</sup> respectively. The PAHs did not exceed the air criteria of World Health Organization indicating the air pollution of PAHs in Riyadh District was not serious. As for the total organic carbon the results demonstrated that the concentration ranged from 0.211 to 0.506 g/kg at KF station and from 0.054 to 0.342 g/kg at AP station. On an annual basis, OC concentrations were two times higher for the city center site (KF) compared to the rural AP site. This can most likely be explained by increased emissions from higher traffic at KF site. The diurnal variability of PM was mainly associated with the severity of pollution.
文摘Boleophthalmus pectinirostris is an amphibious economic fish and wildly distributed in the southeast coast of China. In this study, Aroclor 1254 was intraperitoneally injected into B. pectinirostris with 1, 2 and 4 μg/(g · d) for 28 d to assay the reproductive organ weight, the sperm quality (sperm concentration and motility), and the testicular mitochondrial testicular mitochondria oxidative stress. The results show that the sperm number and motility in seminal vesicles, the absolute weight of testes and seminal vesicles of B. pectinirostris treated with 2 and 4 μg/(g · d) Aroclor 1254 decreased significantly as compared to the controls (p 0.05), while those treated with 1 μg/(g · d) Aroclor 1254 had no significant effects on these indictors. For the relative weight of reproductive organs, significant reduction (p 0.05) was only observed in the seminal vesicles of B. pectinirostris treated with 4 μg/(g · d). SOD activities and GSH levels in all the Aroclor 1254 treatments were significantly lower than those of the controls (p 0.05). The activities of CAT, GPx, GR and the levels of Vit C also decreased significantly in comparison with the controls (p 0.05) at the higher dose of 2 and 4 μg/(g · d) Aroclor 1254 treatments. In addition, both H 2 O 2 level and MDA content in testicular mitochondria of B. pectinirostris had a close correlation with Aroclor 1254 dosage, and were significantly higher than the controls (p 0.05). Those indicate that Aroclor 1254 can induce the oxidative stress of testicular mitochondria, and impair the reproductive function of male B. pectinirostris.
文摘Dietary polyphenols, or phenolic compounds, are numerous, diverse, and ubiquitous phytochemicals occurring throughout the plant kingdom. They are important components of the human diet because of their capacity to reduce the risk of chronic diseases such as cardiovascular disease and cancer. In plants, polyphenols contribute to resistance to pathogens due to their potent astringency and function as phytoalexins. As a result, organic grapevines grown with reduced pesticides may be more stressed by pathogens than conventionally grown grapevines and presumably produce more polyphenols. Since polyphenols also play an important role in the sensory qualities of fruits and wines particularly involving astringency and bitterness, there may be differences that affect sensory perceptions of wine. This establishes a conundrum where dietary polyphenols are healthful but potentially unpalatable.We recruited and randomized 18 female participants (21 - 50 y) to one of five groups (3 - 4 per group). Each group evaluated the sensory qualities of a geographically paired organic (OW) and conventional wine (CW) and an artificially colored white wine placebo (PW) with significantly differing total polyphenol concentrations (TP). Participants reported for three visits (one wine per visit) where they consumed 5 ounces (150 mL) of wine over 15 minutes while completing the sensory survey. Sensory evaluations based on a Likert-type scale included visual, aroma, and taste perceptions and overall impressions (scale 0 - 10). In two wine pairs, the OW contained significantly more TP (3.49 and 5.86 g/L) than the respective CW (2.63 and 4.63 g/L). In two other wine pairs both produced by sustainable viticulture, the CW (5.23 and 8.38 g/L) contained sig- nificantly more TP than OW (4.55 and 3.70 g/L) and in one set the amounts were equivalent (4.10 and 4.17 g/L). The five PW averaged 1.26 ± 0.20 g/L. Although there were significant differences in TP content of test wines, the results indicated that no significant differences in either intensity or quality for any of the sensory qualities were detected be- tween paired OW and CW wines but both scored significantly higher than the PW, with significantly lower TP. We conclude in this pilot study that a subset of OW from the Southwestern US is perceived similarly to CW produced by the same vineyard even with significantly differing TP concentrations.
基金Supported by Scientific and Technological Project of Guangxi Provincial Department of Science and Technology(2007105014)
文摘This article conducts a brief analysis of the factors that affect the quality safety of organic mango, and discusses the organic production measures for improving the quality and quality safety of mango, including the choice of environment of place of origin, varieties and seedlings, fertilizers and fertilization, plant protection products and other production inputs. A test is carried out in 0.667 hm2 of base in Tianyang County, Baise City. Content of lead, arsenic and 14 kinds of pesticide residue such as BHC in the mango are not detected; the content of heavy metal such as mercury and cadmium is 0.001-0.006 mg/kg. Then the quality and quality safety indicators of organic mango are discussed, and finally the Guangxi local standards of organic mango products are developed.
文摘Field experiments were conducted at Tamil Nadu Agricultural University, Coimbatore during rabi and summer seasons of 2007-2008 and 2008-2009 to study the influence of organic manures (enriched farmyard manure compost, vermicompost, farmyard manure + neem cake, enriched farmyard manure compost + vermicompost + farmyard manure, composted poultry manure and enriched poultry manure compost) and recommended NPK fertilizers on yield and quality of rice and blackgram in rice-blackgram cropping sequence. Based on field experiments, it was found that the application of enriched poultry manure compost on equal N basis (2.3 t·ha-1) recorded higher yield attributes and grain yield of rice (4675 kg·ha-1 in 2007 and 4953 kg·ha-1 in 2008), which was however comparable with composted poultry manure. The application of recommended NPK fertilizers recorded higher physical characteristics and cooking qualities of rice, which was comparable with enriched poultry manure compost. Higher sensory score was registered in enriched poultry manure compost as compared to recommended NPK through fertilizers. After harvesting of rice, the residual effect of enriched poultry manure compost and composted poultry manure applied to preceding rice crop improved yield attributes and yield of succeeding blackgram.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61204006 and 61574108the Fundamental Research Funds for the Central Universities under Grant No JB141101the Foundation of Key Laboratory of Nanodevices and Applications of Suzhou Institute of Nano-Tech and Nano-Bionics of Chinese Academy of Sciences under Grant No 15CS01
文摘The effect of a self-organized SiNs interlayer on the defect density of (1122) semipolar GaN grown on 7n-plane sapphire is studied by transmission electron microscopy, atomic force microscopy and high resolution x-ray diffrac- tion. The SiNx interlayer reduces the c-type dislocation density from 2.5 ×10^10 cm^-2 to 5 ×10^8 cm 2. The SiNx interlayer produces regions that are free from basal plane stacking faults (BSFs) and dislocations. The overall BSF density is reduced from 2.1×10^5 cm-1 to 1.3×10^4 cm^-1. The large dislocations and BSF reduction in semipolar (1122) GaN with the SiNx, interlayer result from two primary mechanisms. The first mechanism is the direct dislocation blocking by the SiNx interlayer, and the second mechanism is associated with the unique structure character of (1122) semipolar GaN.
基金Supported by Tianjin Municipal Science and Technology Commission ( No. 033113811) and Young Teacher Foundation of Tianjin University ( No. 985200540).
文摘A new approach to coastal water quality assessment was put forward through study on self-organizing map (SOM). Firstly, the water quality data of Bohai Bay from 1999 to 2002 were prepared. Then, a set of software for coastal water quality assessment was developed based on the batch version algorithm of SOM and SOM toolbox in MATLAB environment. Furthermore, the training results of SOM could be analyzed with single water quality indexes, the value of N: P( atomic ratio) and the eutrophication index E so that the data were clustered into five different pollution types using k-means clustering method. Finally, it was realized that the monitoring data serial trajectory could be tracked and the new data be classified and assessed automatically. Through application it is found that this study helps to analyze and assess the coastal water quality by several kinds of graphics, which offers an easy decision support for recognizing pollution status and taking corresponding measures.