In a long-term experiment carried out between 1967 and 2001 at Hisar, India, pearl millet (Pennis... more In a long-term experiment carried out between 1967 and 2001 at Hisar, India, pearl millet (Pennisetum typhoides) and wheat (Triticum aestivum) were grown during summer and winter in sequence. The treatments consisted of application of farmyard manure (FYM) at rates of 15, 30, or 45 mg ha during both seasons or either of the seasons. In addition to these treatments, an absolute control was maintained without any FYM in any of the seasons to give a total of 10 treatments. In addition two levels of nitrogen (N), 0 and 120 kg ha, were added through urea (46% N) to both crops in 2000. Soil samples were collected from depths of 0-15, 15-30, and 30-45 cm and analysed for diethylene triamine pentaacetic acid (DTPA) extractable and total content of zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu) as per standard procedures. Application of farmyard manure (FYM) significantly increased the DTPA extractable and total content of all the micronutrients studied at all soil depths. However, th...
Soils of Pokhara valley, especially Malepatan, are fine textured silt loam, extremely acidic inna... more Soils of Pokhara valley, especially Malepatan, are fine textured silt loam, extremely acidic innature (3.7-4.0 pH) and are medium in soil potassium content. On-station experiments wereconducted to assess the response of potassium (K2O) and its application methods on potato tuberyield in an extremely acid soil condition. Six potassium levels (0, 50, 75, 100 kg ha-1 as basalapplication, 50 kg basal plus 50 kg top dressed, and 50 kg basal plus 50 kg foliar application)were tested in the experiment for three consecutive years (2000, 2001 and 2002). A randomizedcomplete block design (RCBD) with 3 replications was employed. Variety used was MS 42.Nitrogen (N), phosphorus (P2O5) and compost were applied as basal dose in each plots at the rateof 100 kg, 50 kg and 20 t ha-1, respectively. Three years mean result on the plant growthcharacters revealed that tallest plant height was recorded (33.22 cm) when 50 kg ha-1 potassiumwas applied basally and 50 kg ha-1 top-dressed. The trend was quite ...
Farmers' field experiment was conducted at Outreach sites in Tanahun and Palpa districts of W... more Farmers' field experiment was conducted at Outreach sites in Tanahun and Palpa districts of Western Nepal with the objectives of evaluating the effects of fertilizers and agricultural lime on grain production of the local and improved (Manakamana-1) maize varieties during summer season of year 2003 and 2004. Farmer's practice (without fertilizers) and with fertilizer 60: 30: 30 kg (N: P2O5: K2O) per hectare with or without agricultural lime (4 t ha-1), were the treatments in experimental study that was conducted in factorial RCB design with four farmers as replications. The results revealed that response of fertilizers and agricultural lime was observed significant plant growth and kernels production including varieties in both sites of Palpa and Tanahun districts. The highest grain yield of 5.1 t ha-1 was produced by the local variety when the crop was supplied with 60:30:30 kg N, P2O5 and K2O ha-1 along with 4 t ha-1 of agricultural lime in Tanahun. Manakamana-1 variety ...
An experiment was conducted on Rhodic Ustochrept soil in Central Hill of Nepal growingwheat-mungb... more An experiment was conducted on Rhodic Ustochrept soil in Central Hill of Nepal growingwheat-mungbean-rice in rotation. Grain yields as affected by 28 t ha-1 a of town compost werecompared with the same amount of farmyard manure and N:P:K (120:60:40). NPK producedsignificantly higher wheat grain (3897 t ha-1). Other yield results were at par with one another.NPK produced lowest mungbean yield. After growing second crop fertility seems to beexhausted thus rice yield indicated no notable residual fertilising effect. FYM and town compostleft noteworthy amounts of P, Ca, Mg and K even after rice harvest.Key words: Organic manure; plant nutrients; sustainabilityDOI: 10.3126/narj.v7i0.1868Nepal Agriculture Research Journal Vol.7 2006 pp.49-53
We report a flashlamp pumped mechanically Q-switched (MQS) 2.94 μm Er:YAG laser based on a spinni... more We report a flashlamp pumped mechanically Q-switched (MQS) 2.94 μm Er:YAG laser based on a spinning mirror with a highest output energy of 805 mJ at a pulse duration of 61 ns and 13 MW of peak power at 1 Hz repetition rate. This record output energy was achieved with the use of 300 mm long MQS Er:YAG laser cavity consisting of a 70% output coupler, 7 × 120 mm AR coated Er(50%):YAG crystal, and 4200 rad/s angular speed of the spinning mirror. The pulse jitter was also measured by using optical triggering and was smaller than 10 ns for 150 ns Q-switched pulses, which could be applicable to many laser applications where precise synchronization of pulses is required.
We report the first room temperature gain switched hot-pressed Fe:ZnSe ceramic laser pumped by ra... more We report the first room temperature gain switched hot-pressed Fe:ZnSe ceramic laser pumped by radiation of 2.94 μm mechanically Q-switched Er:YAG laser. The maximum output energy was 1.5 mJ (90 ns) with 15% slope efficiency.
We report optical characterization of Fe:ZnSe hot-pressed ceramics and demonstrate first room-tem... more We report optical characterization of Fe:ZnSe hot-pressed ceramics and demonstrate first room-temperature gain-switched lasing of this new ceramic medium. The maximum output energy was measured to be 0.7 mJ at 3.5% slope efficiency.
We report the mechanically Q-switched 2.94 µm Er: YAG laser with a record 350 mJ output energy at... more We report the mechanically Q-switched 2.94 µm Er: YAG laser with a record 350 mJ output energy at 3 Hz repetition rate with 160 ns pulse duration and ~10 ns pulse jitter for fine synchronization of pulses.
We report the first room temperature gain-switched Fe:ZnSe hot-pressed ceramic laser pumped by 2.... more We report the first room temperature gain-switched Fe:ZnSe hot-pressed ceramic laser pumped by 2.94 µm radiation of mechanically Q-switched Er:YAG laser. The maximum output energy at 4.2 µm was 41 mJ at 3 Hz repetition rate and 120 ns pulse duration. The measured slope efficiency was 25% with respect to the absorbed energy. This technique could be attractive for the future development of high-energy short-pulse solid-state mid-IR systems.
We report the first room-temperature gain-switched Fe:ZnSe hot-pressed ceramics laser pumped by 2... more We report the first room-temperature gain-switched Fe:ZnSe hot-pressed ceramics laser pumped by 2.94 μm radiation of mechanically Q-switched Er:YAG laser. The maximum output energy was 41 mJ with 25% slope efficiency at 3Hz repetition rate.
Phytoestrogens are naturally occurring plant polyphenolic compounds present in high concentration... more Phytoestrogens are naturally occurring plant polyphenolic compounds present in high concentrations in soybean products. Phytoestrogens are divided into three classes: lignans, isoflavones, and coumestans. Nine types of glycoside isoflavones and three types of aglycoside isoflavones are reported in soybean. Soy isoflavones can reduce the risk of a certain type of cancer, cardiovascular problems, osteoporosis, and menopausal symptoms. We irradiated the leaves of five cultivars of soybean with UV-C (260 nm) and determined the effect on concentrations of isoflavone compounds using liquid chromatography–mass spectrometry (LC–MS). Isoflavone concentrations were significantly higher following irradiation, particularly in the cultivar Daepung, which was selected as the best cultivar for high isoflavone induction with UV-C irradiation. Further experimentation with the cultivar Daepung revealed that 20 min UV-C irradiation was the best treatment for the induction of aglycone compounds, and 5 ...
Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxi... more Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxide (9-26% greenhouse effect), methane (4-9%), and nitrous oxide (3-6%) are the three principal greenhouse gasses though chloroflourocarbon and halon are also included as greenhouse gasses but are in very small greenhouse effect. These gasses are produced both from natural process and anthropogenic activities .Increase of these greenhouse gasses from nature in the atmosphere is mainly from the decomposition of organic matter, nitrification and denitrification of nitrogen including respiration by the plants. Anthropogenic production of carbon dioxide is from burning of fossil fuel whereas for methane livestock and paddy cultivation. Agricultural activities mainly use of mineral fertilizer is responsible for nitrous oxide emission. Increase of these gasses in atmosphere increases temperature that further accelerates evaporation of moisture from the earth’s surface. Increase in water vapor i...
Research & Reviews: Journal of Botanical Sciences, 2016
A study was conducted to assess the impact of prosperity realization through irrigation and small... more A study was conducted to assess the impact of prosperity realization through irrigation and smallholder market (PRISM) approach especially in the areas of input supply, production and output market situation on vegetable sub-sector before and after the project. For this study, two districts namely Kaski in the hill and Kapilvastu in the Terai were randomly selected, in which fifteen farmers’ groups with 105 numbers of household head (7 from each group) in Kaski, and 24 groups with 168 household head in Kapilvastu districts were randomly selected and interviewed using semi-structured questionnaires. The project mainly intervened in networking of agricultural supplies to facilitate the small farmers to enhance production and productivity and marketing. The findings showed that all the indicators used to measure the impact on input supply, farm production and produce marketing were improved showing the positive impact of the PRISM project. Almost all the respondents (>92%) replied p...
Rapid growth of environmental problems, economic volatilities, and social changes have increased ... more Rapid growth of environmental problems, economic volatilities, and social changes have increased the scopes of adopting environmentally friendly and resilient production systems. Regenerative farming and forestry practices are such systems appropriate for mountain communities in Nepal. They had performed better with indigenous resources, institutions, and social-ecological systems. Unfortunately, the assets have been degraded to extinction, mainly commencing works of national and international development agencies. Consequently, regenerative practices are disappearing. Despite appeals and commitments, the degradations of the assets are not halted and reversed. This study used secondary sources of data and work experiences and explained the working faults of the external agencies involved in the agriculture, forest, and wildlife sectors. It elucidated that most regenerative practices had sustained well in forest and farm resource-integrated production systems and a modest degree of n...
Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxi... more Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxide (9-26 % greenhouse effect), methane (4-9%), and nitrous oxide (3-6%) are the three principal greenhouse gasses though chloroflourocarbon and halon are also included as greenhouse gasses but are in very small greenhouse effect. These gasses are produced both from natural process and anthropogenic activities.Increase of these greenhouse gasses from nature in the atmosphere is mainly from the decomposition of organic matter, nitrification and denitrification of nitrogen including respiration by the plants. Anthropogenic production of carbon dioxide is from burning of fossil fuel whereas for methane livestock and paddy cultivation. Agricultural activities mainly use of mineral fertilizer is responsible for nitrous oxide emission. Increase of these gasses in atmosphere increases temperature that further accelerates evaporation of moisture from the earth’s surface. Increase in water vapor i...
In a long-term experiment carried out between 1967 and 2001 at Hisar, India, pearl millet (Pennis... more In a long-term experiment carried out between 1967 and 2001 at Hisar, India, pearl millet (Pennisetum typhoides) and wheat (Triticum aestivum) were grown during summer and winter in sequence. The treatments consisted of application of farmyard manure (FYM) at rates of 15, 30, or 45 mg ha during both seasons or either of the seasons. In addition to these treatments, an absolute control was maintained without any FYM in any of the seasons to give a total of 10 treatments. In addition two levels of nitrogen (N), 0 and 120 kg ha, were added through urea (46% N) to both crops in 2000. Soil samples were collected from depths of 0-15, 15-30, and 30-45 cm and analysed for diethylene triamine pentaacetic acid (DTPA) extractable and total content of zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu) as per standard procedures. Application of farmyard manure (FYM) significantly increased the DTPA extractable and total content of all the micronutrients studied at all soil depths. However, th...
Soils of Pokhara valley, especially Malepatan, are fine textured silt loam, extremely acidic inna... more Soils of Pokhara valley, especially Malepatan, are fine textured silt loam, extremely acidic innature (3.7-4.0 pH) and are medium in soil potassium content. On-station experiments wereconducted to assess the response of potassium (K2O) and its application methods on potato tuberyield in an extremely acid soil condition. Six potassium levels (0, 50, 75, 100 kg ha-1 as basalapplication, 50 kg basal plus 50 kg top dressed, and 50 kg basal plus 50 kg foliar application)were tested in the experiment for three consecutive years (2000, 2001 and 2002). A randomizedcomplete block design (RCBD) with 3 replications was employed. Variety used was MS 42.Nitrogen (N), phosphorus (P2O5) and compost were applied as basal dose in each plots at the rateof 100 kg, 50 kg and 20 t ha-1, respectively. Three years mean result on the plant growthcharacters revealed that tallest plant height was recorded (33.22 cm) when 50 kg ha-1 potassiumwas applied basally and 50 kg ha-1 top-dressed. The trend was quite ...
Farmers' field experiment was conducted at Outreach sites in Tanahun and Palpa districts of W... more Farmers' field experiment was conducted at Outreach sites in Tanahun and Palpa districts of Western Nepal with the objectives of evaluating the effects of fertilizers and agricultural lime on grain production of the local and improved (Manakamana-1) maize varieties during summer season of year 2003 and 2004. Farmer's practice (without fertilizers) and with fertilizer 60: 30: 30 kg (N: P2O5: K2O) per hectare with or without agricultural lime (4 t ha-1), were the treatments in experimental study that was conducted in factorial RCB design with four farmers as replications. The results revealed that response of fertilizers and agricultural lime was observed significant plant growth and kernels production including varieties in both sites of Palpa and Tanahun districts. The highest grain yield of 5.1 t ha-1 was produced by the local variety when the crop was supplied with 60:30:30 kg N, P2O5 and K2O ha-1 along with 4 t ha-1 of agricultural lime in Tanahun. Manakamana-1 variety ...
An experiment was conducted on Rhodic Ustochrept soil in Central Hill of Nepal growingwheat-mungb... more An experiment was conducted on Rhodic Ustochrept soil in Central Hill of Nepal growingwheat-mungbean-rice in rotation. Grain yields as affected by 28 t ha-1 a of town compost werecompared with the same amount of farmyard manure and N:P:K (120:60:40). NPK producedsignificantly higher wheat grain (3897 t ha-1). Other yield results were at par with one another.NPK produced lowest mungbean yield. After growing second crop fertility seems to beexhausted thus rice yield indicated no notable residual fertilising effect. FYM and town compostleft noteworthy amounts of P, Ca, Mg and K even after rice harvest.Key words: Organic manure; plant nutrients; sustainabilityDOI: 10.3126/narj.v7i0.1868Nepal Agriculture Research Journal Vol.7 2006 pp.49-53
We report a flashlamp pumped mechanically Q-switched (MQS) 2.94 μm Er:YAG laser based on a spinni... more We report a flashlamp pumped mechanically Q-switched (MQS) 2.94 μm Er:YAG laser based on a spinning mirror with a highest output energy of 805 mJ at a pulse duration of 61 ns and 13 MW of peak power at 1 Hz repetition rate. This record output energy was achieved with the use of 300 mm long MQS Er:YAG laser cavity consisting of a 70% output coupler, 7 × 120 mm AR coated Er(50%):YAG crystal, and 4200 rad/s angular speed of the spinning mirror. The pulse jitter was also measured by using optical triggering and was smaller than 10 ns for 150 ns Q-switched pulses, which could be applicable to many laser applications where precise synchronization of pulses is required.
We report the first room temperature gain switched hot-pressed Fe:ZnSe ceramic laser pumped by ra... more We report the first room temperature gain switched hot-pressed Fe:ZnSe ceramic laser pumped by radiation of 2.94 μm mechanically Q-switched Er:YAG laser. The maximum output energy was 1.5 mJ (90 ns) with 15% slope efficiency.
We report optical characterization of Fe:ZnSe hot-pressed ceramics and demonstrate first room-tem... more We report optical characterization of Fe:ZnSe hot-pressed ceramics and demonstrate first room-temperature gain-switched lasing of this new ceramic medium. The maximum output energy was measured to be 0.7 mJ at 3.5% slope efficiency.
We report the mechanically Q-switched 2.94 µm Er: YAG laser with a record 350 mJ output energy at... more We report the mechanically Q-switched 2.94 µm Er: YAG laser with a record 350 mJ output energy at 3 Hz repetition rate with 160 ns pulse duration and ~10 ns pulse jitter for fine synchronization of pulses.
We report the first room temperature gain-switched Fe:ZnSe hot-pressed ceramic laser pumped by 2.... more We report the first room temperature gain-switched Fe:ZnSe hot-pressed ceramic laser pumped by 2.94 µm radiation of mechanically Q-switched Er:YAG laser. The maximum output energy at 4.2 µm was 41 mJ at 3 Hz repetition rate and 120 ns pulse duration. The measured slope efficiency was 25% with respect to the absorbed energy. This technique could be attractive for the future development of high-energy short-pulse solid-state mid-IR systems.
We report the first room-temperature gain-switched Fe:ZnSe hot-pressed ceramics laser pumped by 2... more We report the first room-temperature gain-switched Fe:ZnSe hot-pressed ceramics laser pumped by 2.94 μm radiation of mechanically Q-switched Er:YAG laser. The maximum output energy was 41 mJ with 25% slope efficiency at 3Hz repetition rate.
Phytoestrogens are naturally occurring plant polyphenolic compounds present in high concentration... more Phytoestrogens are naturally occurring plant polyphenolic compounds present in high concentrations in soybean products. Phytoestrogens are divided into three classes: lignans, isoflavones, and coumestans. Nine types of glycoside isoflavones and three types of aglycoside isoflavones are reported in soybean. Soy isoflavones can reduce the risk of a certain type of cancer, cardiovascular problems, osteoporosis, and menopausal symptoms. We irradiated the leaves of five cultivars of soybean with UV-C (260 nm) and determined the effect on concentrations of isoflavone compounds using liquid chromatography–mass spectrometry (LC–MS). Isoflavone concentrations were significantly higher following irradiation, particularly in the cultivar Daepung, which was selected as the best cultivar for high isoflavone induction with UV-C irradiation. Further experimentation with the cultivar Daepung revealed that 20 min UV-C irradiation was the best treatment for the induction of aglycone compounds, and 5 ...
Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxi... more Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxide (9-26% greenhouse effect), methane (4-9%), and nitrous oxide (3-6%) are the three principal greenhouse gasses though chloroflourocarbon and halon are also included as greenhouse gasses but are in very small greenhouse effect. These gasses are produced both from natural process and anthropogenic activities .Increase of these greenhouse gasses from nature in the atmosphere is mainly from the decomposition of organic matter, nitrification and denitrification of nitrogen including respiration by the plants. Anthropogenic production of carbon dioxide is from burning of fossil fuel whereas for methane livestock and paddy cultivation. Agricultural activities mainly use of mineral fertilizer is responsible for nitrous oxide emission. Increase of these gasses in atmosphere increases temperature that further accelerates evaporation of moisture from the earth’s surface. Increase in water vapor i...
Research & Reviews: Journal of Botanical Sciences, 2016
A study was conducted to assess the impact of prosperity realization through irrigation and small... more A study was conducted to assess the impact of prosperity realization through irrigation and smallholder market (PRISM) approach especially in the areas of input supply, production and output market situation on vegetable sub-sector before and after the project. For this study, two districts namely Kaski in the hill and Kapilvastu in the Terai were randomly selected, in which fifteen farmers’ groups with 105 numbers of household head (7 from each group) in Kaski, and 24 groups with 168 household head in Kapilvastu districts were randomly selected and interviewed using semi-structured questionnaires. The project mainly intervened in networking of agricultural supplies to facilitate the small farmers to enhance production and productivity and marketing. The findings showed that all the indicators used to measure the impact on input supply, farm production and produce marketing were improved showing the positive impact of the PRISM project. Almost all the respondents (>92%) replied p...
Rapid growth of environmental problems, economic volatilities, and social changes have increased ... more Rapid growth of environmental problems, economic volatilities, and social changes have increased the scopes of adopting environmentally friendly and resilient production systems. Regenerative farming and forestry practices are such systems appropriate for mountain communities in Nepal. They had performed better with indigenous resources, institutions, and social-ecological systems. Unfortunately, the assets have been degraded to extinction, mainly commencing works of national and international development agencies. Consequently, regenerative practices are disappearing. Despite appeals and commitments, the degradations of the assets are not halted and reversed. This study used secondary sources of data and work experiences and explained the working faults of the external agencies involved in the agriculture, forest, and wildlife sectors. It elucidated that most regenerative practices had sustained well in forest and farm resource-integrated production systems and a modest degree of n...
Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxi... more Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxide (9-26 % greenhouse effect), methane (4-9%), and nitrous oxide (3-6%) are the three principal greenhouse gasses though chloroflourocarbon and halon are also included as greenhouse gasses but are in very small greenhouse effect. These gasses are produced both from natural process and anthropogenic activities.Increase of these greenhouse gasses from nature in the atmosphere is mainly from the decomposition of organic matter, nitrification and denitrification of nitrogen including respiration by the plants. Anthropogenic production of carbon dioxide is from burning of fossil fuel whereas for methane livestock and paddy cultivation. Agricultural activities mainly use of mineral fertilizer is responsible for nitrous oxide emission. Increase of these gasses in atmosphere increases temperature that further accelerates evaporation of moisture from the earth’s surface. Increase in water vapor i...
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