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DOE OSTI2025

Innovative Polyhydroxyalkanoates (PHA) Production with Microbial Electrochemical Technology (MET)

The project “Innovative Polyhydroxyalkanoates (PHA) Production with Microbial Electrochemical Technology (MET)” addressed food waste disposal challenges by successfully converting food waste to bioplastics (known as PHAs). The novel process created by our team of researchers from universities, national labs, and industry substantially enhanced overall carbon conversion efficiency of food waste processing (> 50%), while reducing disposal costs (> 25%). The project showed economic viability potential at community scale through pilot-scale demonstration at a relevant scale (50 L reactor volume) with more than 100 hours of PHA production using realistic conditions. The project goal was to valorize food waste by shunting traditional anaerobic digestion processing and creating a value-added PHA processing route that improves the economics and sustainability of local, community-scale, wet organic waste treatment. First, the food waste undergoes microbial-based, dark fermentation to break down the food to small carbon chains known as volatile fatty acids (VFAs). Instead of microorganisms converting the VFAs into methane using normal anaerobic digestion processing, our innovative process inhibits methane production. This preserves the produced VFAs for extraction and use by a novel Haloferax mediterranei (HM) archaea, which effectively converts the VFAs to bioplastics. The project added microbial electrochemical cells (MEC) to the dark fermentation process to enhance the VFAs produced and optimize the type of bioplastics formed.

36 MATERIALS SCIENCE↗

DOE OSTI2025

Microwave-assisted delignification for improved cellulose production

This study aims to develop microwave (MW) technologies to improve the paper pulping process, decreasing both chemical and thermal energy requirements. The overall objective is to explore an efficient process that aids in the delignification of paper pulp, reducing energy needs and chemical intensity. The experimental variables evaluated during the MW-assisted digestion process include formic acid concentration, time, temperature, digestion cycles, and the formic acid to paper ratio. This research investigates the potential of MW technology to create a more sustainable and efficient cellulose production method.

microwave heating↗

DOE OSTI2018

Bench‐Scale Evaluation of Hydrothermal Processing Technology for Conversion of Wastewater Solids to Fuels: Marrone et al.

ABSTRACT: Hydrothermal Liquefaction (HTL) and Catalytic Hydrothermal Gasification (CHG) proof‐of‐concept bench‐scale tests were performed to assess the potential of hydrothermal treatment for handling municipal wastewater sludge. HTL tests were conducted at 300 to 350 °C and 20 MPa on three different feeds: primary sludge, secondary sludge, and digested solids. Corresponding CHG tests were conducted at 350 °C and 20 MPa on the HTL aqueous phase output using a ruthenium‐based catalyst. Biocrude yields ranged from 25 to 37%. Biocrude composition and quality were comparable to biocrudes generated from algae feeds. Subsequent hydrotreating of biocrude resulted in a product with comparable physical and chemical properties to crude oil. CHG product gas methane yields on a carbon basis ranged from 47 to 64%. Siloxane concentrations in the CHG product gas were below engine limits. The HTL‐CHG process resulted in a chemical oxygen demand (COD) reduction of > 99.9% and a reduction in residual solids for disposal of 94 to 99%.

Marrone, P. A.↗

DOE OSTI2022

Comparative Study on the Pretreatment of Aspen and Maple With 1-Ethyl-3-methylimidazolium Acetate and Cholinium Lysinate

The efficiency of the enzymatic digestibility of certain lignocellulosic biomass has been observed as a function of their structural and chemical changes which in turn depends on the ionic liquid (IL) used as the pretreatment solvent. This study demonstrated and compared the feasibility of the IL pretreatment process for two woody biomasses, namely maple and aspen, using two mechanistically distinct ILs, i.e., 1-ethyl-3-methylimidazolium acetate (C 2 mim][OAc]) and cholinium lysinate ([Ch][Lys]) as the solvent. The pretreatment was performed at three different temperatures of 100°C, 140°C, and 160°C at a high solid loading of 25 wt% to understand the impact of lignin content and crystallinity index on enzymatic digestibility. Saccharification of the biomass obtained after the IL pretreatment afforded 30–85% glucan conversions. For aspen, both [C 2 mim][OAc] and [Ch][Lys] exhibited the highest glucan conversion at 140°C. For maple, the highest glucan conversion was obtained at 140°C with [C 2 mim][OAc], whereas [Ch][Lys] had an optimum glucan conversion at 160°C. These pretreatments resulted in negligible delignification irrespective of the IL used. A significant loss of crystallinity was observed for all [C 2 mim][OAc]-pretreated biomasses, whereas the pretreatment with [Ch][Lys] resulted in an increase in the crystallinity index.

Choudhary, Hemant↗

DOE OSTI2024

Feasibility of using nuclear microreactor process heat for bioconversion and agricultural processes

Introduction There is a global goal to reduce greenhouse gas emissions by 43% by 2023. Nuclear microreactors, a subset of small modular reactors, offer a potential solution due to their compact size, transportability, and carbon-neutral power generation capabilities. Methods This study explores the feasibility of using heat from nuclear microreactors for bioconversion and agricultural processes, including transforming biomass into energy carriers and products such as syngas, bio-oil, and pasteurized milk. Operating requirements for gasification, pyrolysis, hydrothermal carbonization, hydrothermal liquefaction, hydrothermal gasification, ethanol production, anaerobic digestion, and pasteurization were obtained through a literature review. A Brayton cycle model based on the eVinci TM microreactor was developed to assess the feasibility of powering these processes using nuclear microreactor heat. Results and Discussion Exergetic efficiency values for high-temperature processes ranged from 72% to 100%, whereas lower-temperature processes ranged from 2% to 53%. These efficiencies depend on the available source temperature for each microreactor design. There were trade-offs between producing net power and using process heat, particularly for high-temperature processes. Three heat exchanger locations were considered: before the turbine (600 ℃ ), between the turbine and regenerator (370 ℃ ), and after the regenerator (192 ℃ ). High-temperature processes like gasification require temperatures too high for feasibility. Middle temperature processes are better suited to a heat exchanger between the turbine and regenerator, while also operable before the turbine. Lower-temperature processes like pasteurization and anaerobic digestion can use waste heat after the regenerator and do not impact power production. These findings are valuable for optimizing nuclear microreactor heat use and aligning with global climate initiatives.

09 BIOMASS FUELS↗

DOE OSTI2016

Defatted Biomass of the Microalga, Desmodesmus sp., Can Replace Fishmeal in the Feeds for Atlantic salmon

Microalgal biomass is a potential feed ingredient that can replace fishmeal and ensure sustainability standards in aquaculture. To understand the efficacy of the defatted biomass from the marine microalga, Desmodesmus sp. a 70-day feeding study was performed with Atlantic salmon (Salmo salar) smolts. Three groups of fish (av. wt. 167 g) were offered either a control feed (without the microalga) or the microalga-containing (10/20%) feeds. At the end of the feeding period, the growth indices (condition factor, specific growth rate) and survival of the microalga-fed fish were not significantly different from the respective values of the control fish, but the feed conversion ratios were inferior. The proximate composition of the whole body of salmon from the three groups did not vary significantly. Compared to the control fish, the 10% alga-fed fish had lower lipid content in their filet. The protein and lipid digestibility in the three feeds did not differ significantly, but the digestibility of energy in the 10% alga-feed was significantly lower than that of the control feed. Furthermore, comparison of the distal intestinal proteome of Atlantic salmon revealed that the expressions of Alpha-2-HS-glycoprotein-like (Ahsg), Myosin-11 isoform X1 (My11) and Dihydrolipoyl dehydrogenase, mitochondrial-like (Dld) were altered by the microalgal feeding. Examination of the physiological status of the fish based on the serum antioxidant capacities did not reveal any alga-feed-related differences. Moreover, the expression of the selected immune and inflammatory marker genes and the micromorphological observations did not indicate any aberration in the intestinal health of the microalga-fed fish. It is possible to include 20% of defatted Desmodesmus sp. in the feeds of Atlantic salmon.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2023

Study of unripe and inferior banana flours pre-gelatinized by four different physical methods

This study aimed to prepare the pre-gelatinized banana flours and compare the effects of four physical treatment methods (autoclaving, microwave, ultrasound, and heat-moisture) on the digestive and structural characteristics of unripe and inferior banana flours. After the four physical treatments, the resistant starch (RS) content values of unripe and inferior banana flours were decreased from 96.85% (RS2) to 28.99–48.37% (RS2 + RS3), while C∞ and k values were increased from 5.90% and 0.039 min −1 to 56.22–74.58% and 0.040–0.059 min −1 , respectively. The gelatinization enthalpy (ΔHg) and I 1047/1022 ratio (short-range ordered crystalline structures) were decreased from 15.19 J/g and 1.0139 to 12.01–13.72 J/g, 0.9275–0.9811, respectively. The relative crystallinity decreased from 36.25% to 21.69–26.30%, and the XRD patterns of ultrasound (UT) and heat-moisture (HMT) treatment flours maintained the C-type, but those samples pre-gelatinized by autoclave (AT) and microwave (MT) treatment were changed to C + V-type, and heat-moisture (HMT) treatment was changed to A-type. The surface of pre-gelatinized samples was rough, and MT and HMT showed large amorphous holes. The above changes in structure further confirmed the results of digestibility. According to the experimental results, UT was more suitable for processing unripe and inferior banana flours as UT had a higher RS content and thermal gelatinization temperatures, a lower degree and rate of hydrolysis, and a more crystalline structure. The study can provide a theoretical basis for developing and utilizing unripe and inferior banana flours.

Zhang, Siwei↗

DOE OSTI2016

Transgenic Plant-Produced Hydrolytic Enzymes and the Potential of Insect Gut-Derived Hydrolases for Biofuels

Various perennial C4 grass species have tremendous potential for use as lignocellulosic biofuel feedstocks. Currently available grasses require costly pre-treatment and exogenous hydrolytic enzyme application to break down complex cell wall polymers into sugars that can then be fermented into ethanol. It has long been hypothesized that engineered feedstock production of cell wall degrading (CWD) enzymes would be an efficient production platform for of exogenous hydrolytic enzymes. Most research has focused on plant overexpression of CWD enzyme-coding genes from free-living bacteria and fungi that naturally break down plant cell walls. Recently, it has been found that insect digestive tracts harbor novel sources of lignocellulolytic biocatalysts that might be exploited for biofuel production. These CWD enzyme genes can be located in the insect genomes or in symbiotic microbes. When CWD genes are transformed into plants, negative pleiotropic effects are possible such as unintended cell wall digestion. The use of codon optimization along with organelle and tissue specific targeting improves CWD enzyme yields. The literature teaches several important lessons on strategic deployment of CWD genes in transgenic plants, which is the focus of this review

enzyme targeting↗

DOE OSTI2024

Optimizing dietary rumen-degradable starch to rumen-degradable protein ratio improves lactation performance and nitrogen utilization efficiency in mid-lactating Holstein dairy cows

The dietary rumen-degradable starch (RDS) to rumen-degradable protein (RDP) ratio, denoted as the RDS-to-RDP ratio (SPR), has been proven to enhance in vitro rumen fermentation. However, the effects of dietary SPR in vivo remain largely unexplored. This study was conducted to investigate the effect of dietary SPR on lactation performance, nutrient digestibility, rumen fermentation patterns, blood indicators, and nitrogen (N) partitioning in mid-lactating Holstein cows. Seventy-two Holstein dairy cows were randomly assigned to three groups (24 head/group), balanced for (mean ± standard deviation) days in milk (116 ± 21.5), parity (2.1 ± 0.8), milk production (42 ± 2.1 kg/d), and body weight (705 ± 52.5 kg). The cows were fed diets with low (2.1, control), medium (2.3), or high (2.5) SPR, formulated to be isoenergetic, isonitrogenous, and iso-starch. The study consisted of a one-week adaptation phase followed by an eight-week experimental period. The results indicated that the high SPR group had a lower dry matter intake compared to the other groups ( p < 0.05). A quadratic increase in milk yield and feed efficiency was observed with increasing dietary SPR ( p < 0.05), peaking in the medium SPR group. The medium SPR group exhibited a lower milk somatic cell count and a higher blood total antioxidant capacity compared to other groups ( p < 0.05). With increasing dietary SPR, there was a quadratic improvement ( p < 0.05) in the total tract apparent digestibility of crude protein, ether extract, starch, neutral detergent fiber, and acid detergent fiber. Although no treatment effect was observed in rumen pH, the rumen total volatile fatty acids concentration and microbial crude protein synthesis increased quadratically ( p < 0.05) as dietary SPR increased. The molar proportion of propionate linearly increased ( p = 0.01), while branched-chain volatile fatty acids linearly decreased ( p = 0.01) with increasing dietary SPR. The low SPR group (control) exhibited higher concentration of milk urea N, rumen ammonia N, and blood urea N than other groups ( p < 0.05). Despite a linear decrease ( p < 0.05) in the proportion of urinary N to N intake, increasing dietary SPR led to a quadratic increase ( p = 0.01) in N utilization efficiency and a quadratic decrease ( p < 0.05) in the proportion of fecal N to N intake. In conclusion, optimizing dietary SPR has the potential to enhance lactation performance and N utilization efficiency. Based on our findings, a medium dietary SPR (with SPR = 2.3) is recommended for mid-lactating Holstein dairy cows. Nevertheless, further research on rumen microbial composition and metabolites is warranted to elucidate the underlying mechanisms of the observed effects.

Chen, Panliang↗

DOE OSTI2022

The Supplementation of FloraMax-B11 Did Not Affect the Bile Acid Neosynthesis and the Enterohepatic Circulation in Broiler Chickens

Most probiotics possess bile salt hydrolase enzymes and may increase bile acid excretion and negatively affect fat digestion and absorption. Therefore, the study objective was to determine the time course effects of a commercial probiotic (P) FloraMax-B11 (FM) supplementation on bile acid neosynthesis and enterohepatic circulation in broiler chickens. Fertile Ross 708 eggs were incubated under standard commercial conditions. At hatch, chicks (n = 550) were randomly assigned to 5 treatment groups (n = 5 replicates per treatment group) with 22 birds per pen. The 5 treatment groups consisted of: control group (C, normal water from hatch to 35 days of age without supplements); P3, water supplemented with FM for the first 3 days post-hatch followed by normal water until day 35; P10, water supplemented with FM for the first 10 days post-hatch followed by normal water until day 35; P35, water supplemented with FM from hatch to day 35; and AGP, water supplemented with antibiotic growth promoter (AGP) from hatch until day 35. Ileum, liver, and plasma were collected at hatch, days 3, 10, 21, and 35 post-hatch. The relative mRNA expression of genes involved in bile acid synthesis (CYP7A1, CYP8B1, FXR, FGFR4, and FGF19) and transport (ASBT, I-BABP, OSTα, OSTβ, and BSEP) as well as ileal deoxycholic acid and plasma cholic acid were determined. There was no FM and AGP interaction for any of the response criteria. No FM or AGP effects were observed (p > 0.05) for any genes, except FGF19, which expression was increased (p < 0.0001) in AGP compared to P35. No FM or AGP effects were observed (p > 0.05) for levels of deoxycholic and cholic acids. However, all the genes, deoxycholic acid, and plasma cholic acid were affected by age (p < 0.0001). In general, the data indicate that FM did not negatively impact bile acid metabolism and enterohepatic circulation, which appeared to be age dependent. However, more research should be conducted to confirm these results and investigate the effects of FM on bile acid metabolism, fat digestion, and intestinal microbiota in broiler chickens.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2020

Combinatorial Glycomic Analyses to Direct CAZyme Discovery for the Tailored Degradation of Canola Meal Non-Starch Dietary Polysaccharides

Canola meal (CM), the protein-rich by-product of canola oil extraction, has shown promise as an alternative feedstuff and protein supplement in poultry diets, yet its use has been limited due to the abundance of plant cell wall fibre, specifically non-starch polysaccharides (NSP) and lignin. The addition of exogenous enzymes to promote the digestion of CM NSP in chickens has potential to increase the metabolizable energy of CM. We isolated chicken cecal bacteria from a continuous-flow mini-bioreactor system and selected for those with the ability to metabolize CM NSP. Of 100 isolates identified, Bacteroides spp. and Enterococcus spp. were the most common species with these capabilities. To identify enzymes specifically for the digestion of CM NSP, we used a combination of glycomics techniques, including enzyme-linked immunosorbent assay characterization of the plant cell wall fractions, glycosidic linkage analysis (methylation-GC-MS analysis) of CM NSP and their fractions, bacterial growth profiles using minimal media supplemented with CM NSP, and the sequencing and de novo annotation of bacterial genomes of high-efficiency CM NSP utilizing bacteria. The SACCHARIS pipeline was used to select plant cell wall active enzymes for recombinant production and characterization. This approach represents a multidisciplinary innovation platform to bioprospect endogenous CAZymes from the intestinal microbiota of herbivorous and omnivorous animals which is adaptable to a variety of applications and dietary polysaccharides.

glycome profiling↗

DOE OSTI2017

α-Conotoxin Decontamination Protocol Evaluation: What Works and What Doesn’t

Nine publically available biosafety protocols for safely handling conotoxin peptides were tested to evaluate their decontamination efficacy. Circular dichroism (CD) spectroscopy and mass spectrometry (MS) were used to assess the effect of each chemical treatment on the secondary and primary structure of α-CTx MII [L10V, E11A]. Of the nine decontamination methods tested, treatment with 1% (m/v) solution of the enzymatic detergent Contrex™ EZ resulted in a 76.8% decrease in α-helical content as assessed by the mean residue ellipticity at 222 nm, and partial peptide digestion was demonstrated using high performance liquid chromatography mass spectrometry (HPLC-MS). Additionally, treatment with 6% sodium hypochlorite (m/v) resulted in 80.5% decrease in α-helical content and complete digestion of the peptide. The Contrex™ EZ treatment was repeated with three additional α-conotoxins (α-CTxs), α-CTxs LvIA, ImI and PeIA, which verified the decontamination method was reasonably robust. These results support the use of either 1% Contrex™ EZ solution or 6% sodium hypochlorite in biosafety protocols for the decontamination of α- CTxs in research laboratories.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2013

Processing of Human Reduction Mammoplasty and Mastectomy Tissues for Cell Culture

Experimental examination of normal human mammary epithelial cell (HMEC) behavior, and how normal cells acquire abnormal properties, can be facilitated by in vitro culture systems that more accurately model in vivo biology. The use of human derived material for studying cellular differentiation, aging, senescence, and immortalization is particularly advantageous given the many significant molecular differences in these properties between human and commonly utilized rodent cells1-2. Mammary cells present a convenient model system because large quantities of normal and abnormal tissues are available due to the frequency of reduction mammoplasty and mastectomy surgeries. The mammary gland consists of a complex admixture of many distinct cell types, e.g., epithelial, adipose, mesenchymal, endothelial. The epithelial cells are responsible for the differentiated mammary function of lactation, and are also the origin of the vast majority of human breast cancers. We have developed methods to process mammary gland surgical discard tissues into pure epithelial components as well as mesenchymal cells3 . The processed material can be stored frozen indefinitely, or initiated into primary culture. Surgical discard material is transported to the laboratory and manually dissected to enrich for epithelial containing tissue. Subsequent digestion of the dissected tissue using collagenase and hyaluronidase strips stromal material from the epithelia at the basement membrane. The resulting small pieces of the epithelial tree (organoids) can be separated from the digested stroma by sequential filtration on membranes of fixed pore size. Depending upon pore size, fractions can be obtained consisting of larger ductal/alveolar pieces, smaller alveolar clusters, or stromal cells. We have observed superior growth when cultures are initiated as organoids rather than as dissociated single cells. Placement of organoids in culture using lowstress inducing media supports long-term growth of normal HMEC with markers of multiple lineage types (myoepithelial, luminal, progenitor)4-5 . Sufficient numbers of cells can be obtained from one individual's tissue to allow extensive experimental examination using standardized cell batches, as well as interrogation using high throughput modalities. Cultured HMEC have been employed in a wide variety of studies examining the normal processes governing growth, differentiation, aging, and senescence, and how these normal processes are altered during immortal and malignant transformation4-15,16 . The effects of growth in the presence of extracellular matrix material, other cell types, and/or 3D culture can be compared with growth on plastic5,15. Cultured HMEC, starting with normal cells, provide an experimentally tractable system to examine factors that may propel or prevent human aging and carcinogenesis.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2016

Comprehensive Isotopic and Elemental Analysis of a Multi-Oxide Glass By Multicollector ICP-MS in Isotope Substitution Studies

Multicollector ICP-MS was used to comprehensively analyze different types of isotopically-modified glass created in order to investigate the processes of glass corrosion in the water. The analytical methods were developed for the analyses of synthesized, isotopically-modified solid glass and the release of glass constituents upon contact with deionized water. To validate the methods, results from an acid digestion sample of the Analytical Reference Glass (ARG) showed good agreement when compared to data from multiple prior analyses on the same glass [Smith-1]. In this paper, we present the results of this comprehensive analysis from the acid digestion of six types of isotopically-modified glass and the release of glass constituents into water corrosion after one year of aqueous corrosion.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2015

Characterization of the salivary microbiome in patients with pancreatic cancer

Clinical manifestations of pancreatic cancer often do not occur until the cancer has undergone metastasis, resulting in a very low survival rate. In this study, we investigated whether salivary bacterial profiles might provide useful biomarkers for early detection of pancreatic cancer. Using high-throughput sequencing of bacterial small subunit ribosomal RNA (16S rRNA) gene, we characterized the salivary microbiota of patients with pancreatic cancer and compared them to healthy patients and patients with other diseases, including pancreatic disease, non-pancreatic digestive disease/cancer and non-digestive disease/cancer. A total of 146 patients were enrolled at the UCSD Moores Cancer Center where saliva and demographic data were collected from each patient. Of these, we analyzed the salivary microbiome of 108 patients: 8 had been diagnosed with pancreatic cancer, 78 with other diseases and 22 were classified as non-diseased (healthy) controls. Bacterial 16S rRNA sequences were amplified directly from salivary DNA extractions and subjected to high-throughput sequencing (HTS). Several bacterial genera differed in abundance in patients with pancreatic cancer. We found a significantly higher ratio of Leptotrichia to Porphyromonas in the saliva of patients with pancreatic cancer than in the saliva of healthy patients or those with other disease (Kruskal–Wallis Test; P < 0.001). Leptotrichia abundances were confirmed using real-time qPCR with Leptotrichia specific primers. Similar to previous studies, we found lower relative abundances of Neisseria and Aggregatibacter in the saliva of pancreatic cancer patients, though these results were not significant at the P < 0.05 level (K–W Test; P = 0.07 and P = 0.09 respectively). However, the relative abundances of other previously identified bacterial biomarkers, e.g., Streptococcus mitis and Granulicatella adiacens , were not significantly different in the saliva of pancreatic cancer patients. Overall, this study supports the hypothesis that bacteria abundance profiles in saliva are useful biomarkers for pancreatic cancer though much larger patient studies are needed to verify their predictive utility.

Science & Technology - Other Topics↗

NASA NTRS1975

Energy and Nutrient Intake Monitoring

A passive system to determine the in-flight intake of nutrients is developed. Nonabsorbed markers placed in all foods in proportion to the nutrients selected for study are analyzed by neutron activation analysis. Fecal analysis for each market indicates how much of the nutrients were eaten and apparent digestibility. Results of feasibility tests in rats, mice, and monkeys indicate the diurnal variation of several markers, the transit time for markers in the alimentary tract, the recovery of several markers, and satisfactory use of selected markers to provide indirect measurement of apparent digestibility. Recommendations are provided for human feasibility studies.

Luckey, T. D.↗

NASA NTRS1976

Skylab nutritional studies

Precise nutritional specifications arising from both physiological and experimental requirements necessitated a comprehensive study of the chemical composition of the Skylab food supply. Each of the approximately 70 different food items was analyzed for digestible and nondigestible carbohydrate, and for protein, amino acids, fat, fatty acids, vitamins, and minerals. Menus were formulated to provide at least the National Research Council's Recommended Dietary Allowance of all essential nutrients and, in addition, to provide constant daily intakes of calcium, phosphorus, magnesium, sodium, potassium and protein. In general, the crewmembers adhered to their programmed menus. The ability to swallow and digest food was unaffected by prolonged weightlessness. Taste acuity also appeared to be undiminished inflight. The bone and muscle changes which occurred in previous flights were more pronounced in Skylab. It is concluded that these changes did not develop as a result of nutritional deficit. If such changes are nutritionally related, they point to the existence of nutritional requirements in weightlessness which differ quantitatively from those observed on earth.

Rambaut, P. C.↗

NASA NTRS1978

Remote sensing data handbook

A digest of information on remote sensor data systems is given. It includes characteristics of spaceborne sensors and the supportive systems immediately associated therewith. It also includes end-to-end systems information that will assist the user in appraising total data system impact produced by a sensor. The objective is to provide a tool for anticipating the complexity of systems and potential data system problems as new user needs are generated. Materials in this handbook span sensor systems from the present to those planned for use in the 1990's. Sensor systems on all planned missions are presented in digest form, condensed from data as available at the time of compilation. Projections are made of anticipated systems.

Source record↗